Here's a personal story. I bought a Losi 8ight buggy in hopes to convert it to brushless. I was willing to spend the $1000+ to get everything needed, but I was held back originally by waiting for Mamba Monster to come out. When it did, it had problems, so I was waiting for those to be fixed. And so on and so forth. In other words, the lack of a good reliable and proven 1/8 scale ESC made me wait for over a year.
In that time, the 8ight 2.0 came out. I was lucky I could sell the 8ight 1.0 for the same price I paid for it originally ($350). I'll wait until everything is ready before buying stuff now.
So yeah, if you're not planning to use something, don't buy it now, but wait. In 6 months, you never know what'll happen and prices will likely drop. This industry's always evolving, just like the PC industry (just not as fast).
P.S. Now I'm wait for 8ight 2.0 to come in Kit form before considering (trying to) get into electric 1/8 again. Looks like that might never happen, though, but I'll still never buy a race roller. I wanna put the thing together myself.