I have the Fluval 206 canister, and it sits under my aquarium, out of sight. It is meant for a 60 gallon aquarium, but as your probably know, it is better to over filter your water. The Fluval 106 treats 25 gallon tanks. It is very quiet, easy to clean, and you can adjust the flow rate. You can also customize the filter media if you would like. It is more expensive than a HOB
filter (well worth it in my opinion, I had HOB
for a week before realizing the canister was the way to go). Also, the input and output nozzle are clear, so you have to clean it every month or so to keep it looking good.
In all, the pros heavily outweigh the cons.