I had an FX5 on my old 120g and it worked well. They are, dollar for dollar, the best canisters on the market, IMO. One thing to factor into the cost, however, is the price of the media. I paid $170 for my FX5 and though media would run $5-10. $65 later and a canister about 85% full, I was amazed.
FX5 worked great and still does if I had it setup. It is a great mechanical filter but as far as bio I can't comment as I never used it for bio. The FX5 pumps 900 gph without media and circulates 607 GPH without media as that is what is listed in the instruction manual. My 2262 pushes 925 gph with media at 80 watts and the FX5 is 50 watts.