How much riding do you do? If your a guy that doesn't put on a bunch of miles you should be good for a couple years, put on a few thou a year, definitely would consider a rebuild.
Riding buds had issues with bogey wheels and tweaked suspension parts more than engine issues. Look over the skid well.
The experience I've had with the 800R's were very good (never owned one, rode with a few often). I was always way more impressed with them than the etecs in the performance area, they were a blast to ride and had some good legs top side! Easier to work on/diagnose issues as well.