I bought 1, £80 for a 40 litre. Got it set up and there doesn't seem to be any problems so far.
Only complaint I have is with the filter. It's really large, makes the one that came with my jewel rio 180 look pathetic, which is good. The trouble is with what was in it. There are 3 big compartments, first one has 2 large sponges in, second has a large carbon bag with a few bio-balls, last has 2 huge carbon sponges.
Slightly overdone the carbon there I think. I've ripped all the carbon out as I've put plants in the tank, which means I'll have to make a trip back to the lfs to buy some new stuff to replace it.