I'm gonna come right out and suggest against the reo. It's an amazing product and it works amazingly well every time. But, it has zero safety features and if your atty has a short, you could have serious problems, thermal runaway, catastrophic failure, ect. That's why I suggested against mechs in my earlier posts. If you don't know about ohms law, or battery ratings, which type of batteries to use, or why you should know these things, hold off on getting a reo.
Now, on the other hand, you could learn all of these things with a few hours of solid research, memorizing W = V^2/ohms = A*ohms, understanding the differences between imr unprotected safe chemistry batteries and icr protected batteries, knowing how to translate a c rating into an amp limit, knowing how to check for shorts, and what to do when one occurs, and more. And if you did that, you would be ready to safely use mechs, but that's why they are not usually recommended to beginners.