Are 500 hours too many for a used hi-end cartridge?

Under ideal conditions, top quality cartridges can exceed 2,000 hours of playing life.  But, you have no way of knowing if records played were pristine and impeccably cleaned, that alignment and setup were optimal, etc.  

I would guess that a big consideration is whether you would settle for the cartridge being re-tipped by someone like SoundSmith, which does it for much less than the manufacturer replacing the stylus.  

It will be fair enough to say that you never know the actual usage time in hours if it wasn't counted by the user himself every time he put the needle on the record.

If you will watch certain sellers you will find out that each used cartridge they are selling claimed to be 200 hrs (but in many cases they are second owners and have no idea about actual usage time). Some sellers just love the number 200 and always use it to indicate hrs of use :) 

I bought many vintage cartridges, some NOS, some used, i'm looking for perfect condition and i want to know who is the owner and how many cartridges he's using. If someone like myself have over 30 cartridges then the actual hrs of use will be very low for each one. But if someone using just one cartridge for everyday listening then i will probably never buy it used. 

To insure yourself try to avoid used cartridges with Conical and Elliptical stylus tip (about 300-600 hrs), the life span of those diamond profiles is very short compared to advanced profiles like LineContact, MicroLine, MicroRidge, F.Gyger, VdH, SAS .... those diamonds can be used for 2000-3000 hrs. 

In general i would say 600 for something like Elliptical and 1200 for LineContact, something close to 2000 hrs for MicroRidge and related. 

Just read this article 

I will add short quote from that article, after stated numbers for each profile you'd better inspect it, it does not mean they are worn, but as you can read there are some amount of degradation according to this research from SAS (see below): 

Wear, Tear and Life

So we know that the more extreme line contacts reduce wear.... but what is the difference?

Apparently according to Jico (manufacturer of the highly regarded SAS stylus), the amount of playing time where a stylus will maintain its specified level of distortion at 15kHz is as follows:

• Spherical / Conical     - 150hrs
• Elliptical                       - 250hrs
• Shibata/Line contact - 400hrs
• SAS/MicroRidge         - 500hrs

This is not to say that at 500 hrs a SAS stylus is "worn out" - but at that stage the wear has reached the point where distortion at 15kHz surpasses the level specified by Jico for a new stylus. (Which I believe is 3%).

Some manufacturers have traditionally defined a stylus as being "worn out" when it starts to damage the record... in these terms the figures provided by Jico can at least be doubled, and in some cases quadrupled.

Summary

In pure sonic terms on pristine vinyl a top notch elliptical can do as well as all but the very best Line Contact / Shibata styli, but will ultimately be surpassed by the better MicroLine styli.

However in terms of reduced wear on both stylus and records - the entry point is the Line contact / Shibata category.

In terms of playing back worn vinyl line contact stylus types also have an advantage in that they can contact "virgin" unworn vinyl.

Narrower side radius = improved tracking and reduced high frequency distortion.

Your responses have been very helpful. I think that I will avoid high hours used cartridges. Too many unknowns.
I’m now thinking that about $1000 on something like a new Hana ML or AT ART9 is a better way to go. While possibly not as fine as some $2000 cartridges, at least I’ll be using the cartridge in its prime. And these have great reviews.

My approach, if I were to be tempted to buy an expensive used cartridge where the seller estimates as much as 500 hours of use, would be to suggest to the seller that the cartridge should be evaluated for stylus wear, etc, by a competent third party professional, like SoundSmith for example.  SS provides such a service for a fee.  You could then work out with the seller who should pay the fee for evaluation.  For example, seller pays if SS says the cartridge needs a rebuild; buyer pays at least a fraction of the cost, if SS (or other) says the cartridge or stylus has at least half of its life remaining (or some other similar fraction of its useful life).  The buyer would probably have to state in advance what amount of wear is "acceptable". There are other details that could be worked out between two reasonable sincere parties.  (I am not a lawyer.)

There is no direct correlation between price and quality when it comes to $1000 or $2000 cartridges. More important is perfect tonearm/cartridge matching, capability of your phono preamp if you're using LOMC and your personal satisfaction with one or another model, they can be low compliance or mid compliance, silver soil or copper soil, different stylus profile and overall different sound presentation (different flavor).  

Before you will buy any LOMC ask your dealer about service, because when the stylus will be worn you will have to replace it with equal diamond, you'd be better if the manufacturer can replace old cartridge with new one for special price (many manufacturers can do that), they have special program for upgrade, customer support via their official dealers only. 

Art-9 from your wish list is probably best bang for the buck when you're looking for high resolution NEW low output MC with decent stylus profile. You can also look for Dynavector and Shelter cartridges.