I had a type R, then I got my Q. Exact same box/setup (2.3ft^3, 32hz).
Major improvement I found with the Q. Sounds SO much better, and surprisingly it's louder as well. I had expected the type R to win in the spl department, especially given that i'm only giving the Q 600 watts when it should be running around 1000.
Iv'e also heard the HDC3. You really just need to decide what you want more- IMO my Q sounds much more musical and loves a low tuning (~30-32hz). However, the HDC3 is clearly the winner in output, and can handle much more power. If you only have 1000 watts, definetely get the Q as that HDC3 will want more.