I have an HOB on every one of my 6 tanks but only becasue I must as I use them as hydroponic plant nitrate filters, not mechanical filters, for which in my opinion they do the poorest job. Of those 6 HOB, 3 are AC's, 2 are Aqua-Tech 30-60, and 1 is a Penguin 350. Of all I like the Aqua Tech 30-60 the best as It is the narrowest fitting behind the tank, has the highest container walls preventing over-flow, the most affordable, and so far the most reliable .
The Penguin 350 is a close 2nd but hate that it looses prime so easily when the water level drops.
The AC are my least favorite becasue they are IMO an old obsolete design which I had to modify to get to work right.
If I diden't have the need for a nitrate liter the worst is yet to come