Hey,
I have the same bike. All I can say is awsome!!!!. I've owned it since new and it has been very reliable. The only thing to watch is the lower shock bearing collects water when you wash the bike, and the front wheel bearings tend to go bad frequently do to the fact that the seals don't do a good job of keeping the water and dirt out. I have probably close to 400 hours on it, and the bottom end is still origonal. I've only replaced one intake valve, and normal top end re-builds. I did re-jet it from stock, #160 main, and a #50 pilot. I would say it is the best 450f that yamy built. I've heard of people dyno-tuning the 03's and getting over 53 hp. out of a stock engine. As for how I ride it, pretty hard. I used to race it every weekend and it never let me down. One thing to note though, some early production 03's had sticky shifters. Sometimes it would not return. This was caused by a simple burr on the shifter shaft, easy to fix. They fixed this problem for later production 03's. With regular maintanence, you will get a liftime of riding out of this bike. The bike handles like it's on rails, basicaly just point and shoot. Just make sure you set the suspension up properly including race sag. I use 5wt. fork oil at a 135mm level. 3.5" of sag. I'm 6ft, 180 pounds.