Benefit of low output moving-iron Grado ?

Not sure what loading is... or if my phono card is capable of being set to different loads (if loading takes place in the phono stage, that is). Could someone inform... thanks

Well, gosh. After reading such things as the Wikipedia article on cartridges (duh), and some various debates on forums... I feel that it is no wonder that nobody has responded yet! I am a little better educated on the matter now, so perhaps I can restate a few things. Apparently moving iron is pretty much a moving magnet in slightly lighter clothing. Therefore, I can only assume that Grado offers their select MI cartridges in both .5mv and 5mv versions, at exactly the same cost; so that the clearly subjective matter of choice between the two would depend on such things as the phono stage and other equipment, likely purchased to accommodate personal taste in high or low output cartridges.
My phono stage is a MM "phono card" which fits into my integrated 2010s Exposure amplifier, and is manufactured as an option by Exposure. I could buy the MC version for about $250 (would the MM phono card I've got handle a .5mv MI cartridge?). Maybe a relatively inexpensive $250 phono stage is better suited to a high output cartridge anyway?
My turntable is a Music Hall mmf 7.1 with the arm that was included. The Grado Sonata 5mv MI cartridge cost roughly half what the turntable and arm cost. Perhaps an upgrade to the Grado Master, while affordable for the reason of a "re-tipping discount" available for existing Grado cartridge owners, may be money unwisely spent. I couldn't afford a whole new table right now, but the cartridge upgrade could be possible, and I've used the cartridge fairly regularly for about five years now and is sounding worn. Perhaps the entire system I've got wouldn't benefit from a cartridge upgrade and I should just get another Sonata? Maybe the Sonata is the best my current turntable can handle?
So, treading dangerously close to restarting what is surely an old and well-worn debate on high vs. low output; I probably just sound like I don't know what Shinola is, or what it's not. But my current question is in earnest: judging from the system I've got, is it worth it to buy a cartridge priced nearly what the turntable + arm cost?
Sincerely awaiting advice,
Nicky

Thanks, Photon46 for the valuable info; very relevant. In fact, since my initial writing I realized that an operative consideration in all of this is the phono pre-amp. I looked around a little and read about the Grado Ph1 MM/MC preamp which seems like a deal and would theoretically be pretty well matched to a Grado cartridge. Since you also mentioned the fallibility of theories, perhaps someone could vouch for the particular combo of Grado Master .5mv and Grado Ph1 phono preamp? I live a distance from anywhere I might be able to audition stuff (and we have no car), so I rely a lot on research on the web.
Another side question I've got is about cartridge setup. I see that there are two screws on the top of the tonearm which go into the cartridge. If the cartridge I buy weighs exactly the same as the old one, wouldn't installation be as simple as removing the wires from the old cart, unscrewing the screws, and installing the new one in the same way? I wouldn't need an entire setup procedure from a professional, would I?
I have to admit I've never even heard a low-output cartridge and I'm going on research alone that it might be something I'd like. And with Needle Doctor's deal on trade-in cartridges along with the still-affordable phono pre-amp upgrade, it seems doable and worth the potential error in judgement. I could always trade-in the Master Standard for a Sonata Reference for the additional $450 if I'm unhappy, I suppose. And it's not like that's small change for me either, that's three weeks salary! I guess I suffer from the bug like anyone, and I find great enjoyment in listening; always have. Thanks for the heads up on the "cohones" issue! Very glad to have gotten these responses folks, thanks....

Thanks again, particularly Photon. The 1.5mv version isn't listed on Needledoctor's website, but I read an old forum elsewhere (from 2003) that they've "not discontinued them yet". Presumably this means I could get the retip price at N.D. AND get the 1.5mv version, which sounds like a reasonable idea.
I have found out that the settings on the Grado Ph1 are simply "low" and "high", with some confusion about which setting to use for a 1.5mv cartridge (it apparently depends on whether the 1.5mv cartridge is considered high or low output!). I wonder if a lack of gain-setting increments might cause a 1.5mv cartridge to hum?
Also, after reading my turntable's instructions, Music Hall recommends having a professional install anything other than what the factory installed. There is a screwplate through which the screws pass on the top of the headshell. Perhaps this screwplate moves around, and WOULD move around once the screws were removed? Maybe I could remove them gently without disrupting the position of this screwplate? I am worried I would mess it up... and I have no protractor or anything. I do know an audiophile who passes through my town sometimes, I could ask him to help if you folks think I should. I AM a novice.
Also, indeed my cartridge is .5 gram lighter than the newer Jarrah wood models, so the rebalancing you mentioned would be required - this I think I can handle.
Positive news: the retip price is fully $80 less than what I thought it was. Realistic news: time to start saving for this stuff. Thanks, Nicky

"Sound" advice, Photon. Until I'm in a position where amp upgrades are feasible from top to bottom, it seems clear I should stick with the high-output cartridge realm of analogue enjoyment. When it comes down to it, the Sonata has always sounded banging through my Vandy 3a Sigs, and a new, DEPENDABLE cartridge would breathe new life into my system. I am glad you are able to frankly and wisely share your experience with me in our comparable situations (though it looks like your system rocks pretty darn hard). And as far as the setup goes; you're right - the only thing I have to fear is fear itself.
So I suppose all my questions are answered, and perhaps I'll check in again, or send you a personal note once I replace the cartridge. Peace, Nicky

Bad writing skills, Nicky. What I meant by "dependable" was a modest upgrade (the high-output Master) which would be SIMILAR to what I've got and have been happy with (the Sonata), without gambling on a new phono stage. Whew...

Thanks to both Atmasphere and Fourwinds. Atmasphere: in another universe I would be a proud owner of your equipment, from phonograph down through amplifiers. Alas, it cannot be! I am thinking of asking Acoustic Sounds (where I bought my turntable) to set up the new cartridge when the time comes. Perhaps they might be able to fiddle with the loading on my preamp at their discretion.
Fourwinds: thanks for the heads up on Dynavector... I've been meaning to look into their stuff. The 20x2 looks good, and is advertised to work with "most" MM phono stages. Is this accurate?
If others are still reading: what about these cartridges from London Decca? The "Maroon" is in my price range, and with some saving, even the "Gold". They are both 5mv output, which makes me happy. I just don't know how reliable they are. Anyone care to weigh in on London Decca vs. Dynavector vs. Grado? (p.s. NOT getting rid of my not-so-polite Vandersteens anytime soon!)

Advice noted. I will ask my dealer if I would need a MC preamp for the Dyna, but hopefully it is robust enough for my MM phonocard. I guess I do have to admit the "sparkle-lacking" qualities of the Vandersteens; it's funny how I lack objectivity in direct proportion to the amount of money I spend on something!