I'm running an aquaclear 70 hob
on my 46g. The filter compartment is HUGE. I have a 70 sized sponge, 70 size carbon, 70 ceramic rings-they call them biomax, a 30 sized sponge and a 30 sized carbon from an existing filter to help with the seeding.
I have it running on low and it kicks. On the other side of the tank I have a dirt magnet sr for extra bio filtration - it runs with an air pump. I recently added a flexible weighted bubble bar, but that is just because I like the bubbles and the fish seem to as well.
My tank cycled in less than a week (I seeded my new filter on an existing tank and used some seeded materials in the tank as well, I also after that week just to be safe added some bio-spira) and has had happy inhabitants for 3 weeks now. I'm just getting ready to finish stocking it.
Good luck on your choice. I know the agony you are going through.