Got it. Then, if you are the type of person who likes training with data and/or wants to use a structured training program, get a power meter. If you like to "just ride" for training and ride whenever you feel like it, and wouldn't really use the power meter except for as a glorified bike computer, then get the fast wheels. A power meter is also an incredible pacing tool, but that's more relevant for ironmans and half ironmans than for sprints.

If you're doing a structured training program a PM will make you go faster than fast wheels will.

Personally, I'd rather ride a 25 pound steel bike with a power meter than a 15 pound bike without one. But I have a teammate who is a heckuva lot stronger than me; he'll ride 2 hours one week and 16 the next, and he doesn't train with power. It wouldn't work for him, so to each his own. I threw my assioma pedals on his bike once for kicks and he did 384 watts for 20 minutes. I almost quit cycling altogether after that.