down firing or front firing sub?

Which do you prefer in your application and why?
Downfiring gets the maximum room loading/efficiency and minimizes the audibility of higher harmonics (due to distortion).
I tried my Rega Vulcan downward, frontward, backward, sideways, ... found it worked best for me in my room firing backward with the cone alligned somewhat with the plane the rear port of my mini monitors are in...
I would say play around and see what happens.. I have my sub sitting on 3 walker cones going into a rug. Not using the feet of the sub itelf.
Down firing is better for music because it blends more seamlessly with the main speakers.

Forward firing is better for HT.
Down firing, because I can simply turn it upside down and put a weighted board on top and achieve much better performance. With a front firing sub you would have to raise it up on blocks or something to get it off the ground.
It depends on the application. All good points above, but, in some instances front firing sub(s) might have some advantages. Those that have neighbors below them, might find front firing subs more suitable. So might those that might not have the firmest flooring. In the near field a front firing sub might offer better driver integration with the main speakers.
If you're crossing low enough (<80hz or so), I suspect that the distinction isn't terribly meaningful. If you take the same sub and position it both ways (some models are designed for this), I'd have to think that room position would have way more impact than driver orientation.

That said, I've never done the A-B, so take this FWIW>

Thanks for the responses guys. I'm looking at constructing my own with a tapered back chamber with the Rythmik 12" + direct servo amp and position will / could have a bearing on its outer construction.
The only reason I'd avoid a down firing sub is if someone lived below me. Aside from that, both can sound good. Taste and budget are going to be your final qualifiers.