The first model year for every sled has it's bumps (08 for the XP Summit). the motor, the 800r first appeared in the 07 summits and that is when it was having bearing problems. No engine issues in the 08.
There was only one recall that I remember on the 08 and that was the driveshaft - they had lots of them breaking. But if that was fixed you are good there.
The clutching had 2 issues, 1 the clutch tower flexes under load, causing the belts to heat up real fast and blow more often. There is a brace available from sledheadracing.net that takes about 15 minutes to install and eliminates this problem.
The only other issue I can recall is the suspension. Both the 08 and 09 have not the best suspension setups. If it is an X package no big deal because you can revalve the shocks for around $200 for all 4 and have most of the issues fixed. If it is not an X package, you should put new shocks in your budget (at a minimum the rear skid and maybe the front as well - $600-$1200 for new shocks). You will definitely be able to ride it as is, but the ride will greatly improve as well as your ability to carve. (when riding stand about 8-10" back from the front of the running board and tilt the bars back - this sled is not meant to be ridden like a rev with your feet locked into the toe holds).
I had an 08 146 Everest and now have a 09 146 X-package. Here are some little things I have noticed:
1) Check the y-pipe bolts and even add nordlock washers (do a search on dootalk for the part number available from fastenal). My y-pipe fell of on the 08 and it started my sled on fire. The y-pipe falling off is common, starting on fire is not as common (see the end of the video:
http://www.youtube.com/watch?v=82wxUymqIHk)
2) Watch the controls with snow. My kill switch ALWAYS freezes so make sure it is in the "ON" position when you go in for the night. And I have had the lights and RER do some weird things when I roll the sled a lot (I might be a little rougher on these parts than most).
I loved both sleds, and you will definitely be happy with either one. After looking around dootalk and snowest, that is a good price for a sled with that few miles on it.
When checking over the chassis pay close attention to where the A-arms connect to the bulkhead. That seems to be an area that tears quite a bit.
Let me know if you have any other questions... It is a great sled and I am sure you will love it!
Blutooth