I have the big CPR one with the Aqualifter pump... do not get it for two reasons. The pump and cleaning ability. The pump clogs constantly even if you are running a prefilter and decreases the suction of water out of your tank, thus overfilling it with return water from your sump. Not too cool...
Secondly there is no way of cleaning it inside! If anyone has any ideas or recommendations of how to do this please let me know. If you look at the CPR ones, there is no way to get even a long bendie brush up to the top of the overflow. No way at all! So how do you clean it?
Sorry to go on a tangent, but I hate these things, not very well thought through. Can't wait to replace mine. Just don't have the money right now to buy something new! I will get a lifeReef soon. They even have a no-fail guarantee. That's pretty cool.