are these good selds
well tehya re askin 1000 and has studs adn comes with cover

are they pretyt fast
could they beat a 96 formula Z 583cc or a 98 zl440 snopro?

Should be neck'n'neck with the Ski Doo and out in front of the 440 fan. There was no ZL 440 snopro, but there was a Z 440 snopro with a 440 fan cooled. A ZR 440 snopro was the factory pro 440 race sled. The motor is liquid cooled and similar output to the 580. Both snopro's will out handle the EXT hands down.

I don't particularly care for that sled. My dad has the same sled, and it seems like we are always working on it. (then again, it is a snowmobile)

I hear that that model of sled had way too much engine vibration and it screws the carbs up. I don't know if thats right or not. My dads sled is pretty quick though.

my brother has a 95 arctic cat 580 ext.....its a very reliable sled....it was sitting all summer and i just went out the thing fired up first pulll....o yea engine vibaration....someones outa there tree....i meen once ya hit top on it yea it starts vibrating hard......its a pretty fast sled....i hit 106 with it before......but u deff need a clutch kit because the low end is terrible..... Good luck