Stay away from the powersweep. The maxijets are good. I use them for just about everything. I like the quiet one pumps for return pumps, but only because I can get them at petsmart... I am sure there is better. What size will depend on the flow you want through your sump, and how much your overflow can handle. For a 46 you should be looking at maybe 250-300 gph
at whatever height your return will be. For an overflow I would get something that could handle 750 gph
... now for circulation inside the aquarium you could use the maxijets with the propeller to give you more flow, or the hydor korilias, even better would be mp40s if only I could afford them...