Merlin v. Lifegard 300?

Anyone have experience with either or both of these fluidized filters?

I'm considering adding one to my 150g show tank at my office...
probably with a Rio Aqua submersible water pump.

Any comments on build quality, durability, functionality, ease of
setup or maintenance? They both run about $60, plus $16 for the pump.

I'm leaning towards the Lifegard 300 because it seems to have a higher
capacity while hanging snugger behind the tank (I'm doing the hang on
mount).

Here's a link to the site I'm considering purchasing from.
http://www.drsfostersmith.com/produc...=6&pCatId=8756

Thanks in advance.