Go for it! Just make sure you know exactly what you want. Geometry is very important for me on a fast bike. If you need an excuse for fitness cross training works. I ride at least 5 different style bikes. My race bike requires more flexibility and balance and because I am sprinting most of the time, I only ride it a few hours at a stretch . It's a different work out than 8 hours on my touring or mountain bike. Fast is fun. Just make sure you are only as fast as you can control.