David, it's an '04 S4R which was the top Monster at the time with the liquid-cooled 916 superbike motor. This one has exhaust and chip so it's dyno'ed @ 110hp at the wheel. Roll-on wheelies all day long.
The current ('08) top-dog is the S4RS which has the 996 motor and full Ohlins suspension. 130hp stock and the best naked superbike they've ever made. Those are tempting to buy used, hell, all of them are right now. It's a major buyer's market for toys at the moment.
This is the other one I'm looking at, it's a 2000 900ie for a lot less $$. Not the beast that the S4R is, but cheaper all-around, (purchase/maintenance/insurance). Both bikes are practically cleaner than new, owned by fanatics who were generous with the credit card for upgrades:
