Powersweep pumps?

[CHEAPREEF]

What do you guys think about these? Are they any good? I need to increase the flow in my tank, i was going to run a closed loop of sorts but i really don't have the time to put one together right now. I was thinking of adding two of these. http://www.jlaquatics.com/cgi-bin/sh...logno=zm-ps214 This is on a 40gal cube 24"X24"x18"H with a mag7 as a return right now i only have about 400gal of flow back into the tank. Thanks for ay info.

Clinton