I have bought 2 escs from different sellers, one esc says 7,2v max and the other says 14,8v max, but both are completely equal, someone tested this escs and could tell me the real difference?

I always wanted for a good and simple Spitfire kit or ARF for small size engines .25 size, specially model XIV or XIX the most beautifull in my opinion, but... it never happens, and I have tryin it for 15 years, so now.... I decided to do it by myself. My intention is not to make a detailed scale model, but do a simple scale and clean racer model.
Here are some shots of the project start.