Cardas Phono Cartridge

A while back I purchased a Rega P9 table that came with a Cardas Ruby cartridge.  I didn't know how much use was on the cartridge but it sounds great and is a much nicer cartridge then any I had used in the past.  This is really an expensive cartridge and I'm wondering how to know when it should be repaired?  Where do you send such a cartridge to be repaired once it is worn?  Thanks for any input that anyone can offer on this.  I know that it can be rebuilt by Sound Smith but that's not quite the same is repaired by Benz and I saw they don't offer that service any more.
Its a modified Benz cartridge....send it to Soundsmith.
If you send it to Benz, be prepared to purchase an interim cartridge as turnaround is very slow.  It's a Benz Ruby cartridge is a myrtle wood shell.
I was going to say Cardas? makes cartridges?

Send it to Soundsmith. Benz doesnt do rebuilds anymore, only tradein/trade up. Not sure if you can even use it for trade up/in since its been modified by Cardas. If the suspension is shot, and Benz won't allow trade on it your going to have to get a new cartridge.  Good news is Soundsmith does great work with one year warranty.