I bought my 1st Ultra in 1997 with 600 miles on there, an SP, 144 studs, Hot Seat clutch kit, it was pretty quick, at 1800 miles I piped it with Aaens and slapped on SLP Ultra Lite skiis, HUGE difference! Handled 10x better with the skiis, and pipes were fast. I melted part of a piston down at about 4k miles after I was running WOT on a warm day on Lake Bemidji, after it cooled down it fired up, I continued to ride it w/o problems even though the piston was bad, but it didn't seem to affect anything. At about 5k miles I sank it in Yellow Lake Wisconsin, dried it all out and continued to ride it for another couple years, at 10k miles the water pump failed, and cacked a couple heads. So I sold it for $800 and bought a SKS with 3k miles which I put another 5k miles on before I popped a piston due to soapy water after bringing to the car wash due to oil caddy failure....
The only thing I would change with the SP would be:
-Plastic skiis
-Upgrade to Xtra-10 Fox in the front.
Nice sleds!
-Skip