So now I'm not sure should I get a gerbil or a hamster?

I want an animal that can go in one of those cages that you can add climbing tubes to, so can gerbils and hamster climb through the tubes? and do hamsters really bite as much as I've heard? Which gender should I get males or females, like which are more tame, and less smelly? So pros and cons of both would be great, thanks in advance ♥Natasha