i have an aquatop uv-400 and i LOVE IT. LOVE. IT. XD
it's completely silent [in my bedroom, so it has to be!], very efficient and large media-room. i freaking love it all around, but i recently accidentally broke the glass sleeve and uv light while cleaning it :c but all the pieces are otw, and i sealed everything temporarily so i could set it up again. i had to epoxy some of the connectors after breaking them, too. they have everything made so you can really take it apart&clean it, but i managed to crack the delicate plastic on some of the pieces and had to seal them together. mine came with a missing part, which is why i broke it; horsing around trying to figure out why the heck it wasn't fitting properly. not all the pieces are so delicate, though; all the problems i had were on the spray bar. otherwise it's been sturdy. i was new to canisters when i got it, but even with other good reviews for fluval&& the like, i will probably stick with aquatop ♥ mostly because of how quiet; i'm really interested in hearing if the larger models are loud.