Anyone with a high-end home theater sans sub?

It would be worth borrowing a sub to see what if any difference exists.

Yeah, you defintely need powered sub(s) to help that sytem respond like the soundtracks were designed, that's all. If you like what you hear, then it's all good. However, you are indeed missing the full impact of what's intended...nothing more, nothing less.
To say what you have is better or worse, is subjective. But the companies mixing your soundtracks would definitely agree you don't have it set up right.

You can't make a blanket statement like "All home theater needs a sub." My main speakers are Meridian DSP8000s and there is absolutely no need for a sub - they are flat to 18 Hz in my room, up to 118 dB (God forbid). My Meridian 568.2 is programmed to send all frequencies below my crossover setting to them and, believe me, it's high-end home theater.

Rex,
As John points out about his DSP8000's, I used to have these 8000's in my theatre and swapped them out for what I have now. When you have these speakers; there is NO need for a sub. They are full range. My system now is even more dynamic and bass accurate then when I had the 8000's in my room, because they were over powering. I have had a Revel sub in my system and as good as it was, with my current 5 channle full range set up, I do not miss a thing.

Like a hitchhikers night out here!

I have some of the processing some of the meridian owners here have, plus a pair of Sophias, which have all the bass I need for music, however much like a listening session I did with a pair of excellently set up DSP 7000 (one drop down from 8000) the bass was good enough but not heavy enough to carry a lot of the LFE I seem to get in the action movies I watch.

I know Adidadi has a smallish room so his 5200s can make great use of it and pressurise it. I guess it depends on your room - and your taste.