Dynavector or Grado ?


I plan on purchasing the VPI Superscoutmaster and prefer to have the cartridge mounted by VPI before it is shipped to the dealer.
VPI will mount Dynavector and Grado cartridges ONLY as they are the 2 brands they sell.
Query...which is the better sounding cartridge?
The high end Dynavector lists for $4000 and the high end Grado lists for $2500.
I only listen to rock and roll music.
For reference, I have an Arcam FMJ pre amp. with a phonostage and Arcam FMJ mono amps.
Thanks for looking!
theaquaman
Aquaman, just a few follow-up thoughts:

1. The on-line owner's manual for the Arcam FMJ two-channel stereo preamp indicates that the MC phono stage is designed to accommodate "low output cartridges." That is a good sign. If you have any doubts about your phono stage having sufficient gain for some of these low output MCs, it is probably worth a call to your Arcam dealer to inquire about the gain of the Arcam phono stage module.

2. Based on personal experience, I can vouch for the exceptionally linear frequency response of the Dynavector XV-1s cartridge. It is not bright and forward sounding. It is also not lean in the bass frequencies. The cartridge is as extended at the frequency extremes as any I have heard, and the frequency response of the cartridge sounds dead neutral to me. I don't have any experience with the cartridges further down the Dynavector line, so I can't offer any comment on those.

3. If you choose to go with one of the Dynavector cartridges below the XV-1s, you will find that some of those cartridges are just a tad bit light in weight to make for an absolutely perfect match with the JMW-9 tonearm. Assuming I am right about that tonearm having an effective mass of 11g, you will find that most of those cartridges would probably benefit from the use of one of VPI's 3g stainless steel cartridge weights. They are specifically designed to allow the VPI tonearms to pair more ideally with light low compliance cartridges such as the Dynavector Te Kaitora Rua or the XX-2, for example. VPI's web site indicates that the cost of one of these 3g weights is $15 retail.
TheAquaman, I don't think that the problems some others have mentioned about Grado are relevant with the JMW-9 arm & VPI table. I have a Grado Sonata in a Scout and the "Grado Wobble" has reared it's head on one lp out of probably 500 lps I've played, Ormandy's "Finlandia" on a half speed mastered issue. Hum is a total non issue, it's dead quiet. I'm not very familiar with Dynavector's line, so I can't comment on a heads up comparison. I say make your choice on sonic preferences rather than concerns about compatability.
Theauqaman / tpsonic.
You've reminded me of the macro issue. This I think is an interesting and useful forum, but it is biased by the folks who profit from the sale of all things audiophile (moderators) & if you are hunting for Trolls it is probably the most target rich environment on the internet.
The combination of strong financial interests creates a bias toward "True Believers" & a lot of folks are encouraged to throw dollars at fringe products that are of dubious value.
In interest of open and unbiased communication, should there be a disclaimer in the banner on the forum topics list?