I think you're going to discover that you haven't been working on your bow muscles as much as you think. Even switching between bows, the different power cycles can throw a person's muscles off.
I would definitely get a single cam. Since you will be shooting it a lot, I suggest replacing the ever stretching Fast Flight string it will most likely have with 450-Plus. Otherwise you will be spending more time retuning the bow than shooting it. Fast Flight's stretching cost me a record book buck.
There are many things going on in a bow that make them more forgiving of mistakes or faster. You want as fast as you can get but at the same time you want one that will be able to hit a target if you weren't doing something perfectly.
I don't know of any brands to stay away from. But watch out for pro-shops that try to push off brands because they make more money on them or have an old used one in stock they can't get rid of. Martin, Matthews, PSE, Fred Bear, Buckmasters (made by Bear), Golden Eagle (division of Bear), Reflex, Browning, Oneida, High Country Archery and Alpine Archery are all brands I'd have no problem trusting.
I don't think I've ever heard anyone cussing their Matthews.
Don't try to spend the most money you can. Bows in that price range tend to not be forgiving of beginner mistakes. Save that for your second bow. The best thing you could do is find a pro-shop that has an indoor shooting lane.
Get a stabilizer and use a release. Those two items will go far in letting you hit where you're aiming.