Good questions Rick, for me I don't think the HSF stuff would look that bad. My back screen wall is painted flat black and my side walls ceiling are painted a dark navy blue. Since this room is a dedicated HT room, like a theater, it might work for me.
The sample audio clips are amazing what they did for the guitar and drum. I'm going to try the real traps test tones one more time with the 500 in the corner and compare to the other locations. Who knows, maybe I'll make some DIY treatments to see what happens, might be hard to beat HSF prices though.
I'm sure the 4' x 8' pool table I've added will change things also.