You can use them they generally are just a little smaller in cu.in than those that are outlet boxes. Bottom line get a good size box for your receptacles a good one is the carlon blue 22 cu in outlet/switch box....
junction boxes suck, don't put any in on a new installation..... also, plastic boxes are the way to go on residential. also, think about it like this, if you have 12/2 running into your panel, you want to run #12 for that whole circuit, if you have #14 going to the panel, you want 14 for the whole circuit.
i got 20 22cu" dark blue Carlons now, so gray for the switches, blue for the outlets, yes? i got the deeper boxes because i will be using mostly 15a gfci outlets and they seem to be more comfy in the bigger boxes...lol.