Unlike most of these debates I own both sleds in question. I have been riding Vipers for years and also owned a 2002 SRX but I have recently started collecting older sleds including a 1980 SRX, a 1987 Vmax 540 and a 1994 Vmax4 750, (also a non Yamaha 1988 Polaris 650 ). I just took the 94 Vmax4 out on a beautiful flat, hard packed lake here in NH. and was blown away! The SRX and Viper hit hard and settle down to easily pull to 100+ MPH but the Vamx4 is totally different, partly due to a stock track and no studs you have to creep up on the throttle but once it starts going it is like a freight train and seems to pull harder and harder the longer you hold it. I understand track spin and inaccurate speedos and all but the needle just kept going 100, 105, 110, 115, 120! and then i ran out of lake. I am looking for opinions on Viper vs. Vmax4 I love them both but can't race myself lol!