You'll want to check the serial number to see if it has a plastic or steel cam gear. Plastic cam gears have been problematic.
If it has a plastic cam gear, and it fails, that is not an inexpensive repair.

I have had my GX-345 since Feb 2005 and it is still a fantastic Lawn/Garden Tractor. I only had one minor, known issue with it several years ago and I was able to correct it for around $50.

If the unit you are asking about is in good shape, I would think it is an excellent value.

Good luck !!!