I really like my new sponge filter, but I don't know the brand or anything since I got it secondhand. I also really liked the Tetra Whisper 3I pair that I had in that same tank. Other than that... I love my QuietFlows! I've had three and loved them all.
On that^ note, I really really like my Aqueons. They're not Pros, but they're great! They don't break the bank, either. The only other kind I've tried was a Hydor Theo, which overheated and nearly killed my boy after two months.