I think I have the 2nd or 3rd pair of HT2-TL's (I received mine 3-20-09).
While I agree that the bass is very capable with the HT2-TL's, they work MUCH better with an EQ'd subwoofer (or 2 in my case). I was able to measure down to nearly 20Hz at reference level in my room.
The HT2-TL's are rather easy to over-drive, as I know a few of us that have done so (without any damage). Now, paired with my subs, this is a completely different story. The important things are to have high quality subwoofer, proper placement and setup, and EQ'd. I couldn't be happier with my setup with the subs. You'd never know the subs were playing other than the clean, deep bass that comes from them.
The Rythmik F12 is a very good subwoofer. I'd bet anything your issues with it come from poor in-room frequency response. EQ that sub in the right place in your room, and you'd be saying something completely different.
