older speaker designs

thanks for the detailed explanation of why "not to worry". As I mentioned I've been out of hifi for some time, and coming back it's easy to get overwhelmed by the "hype" of why one is better thank the other. 
My required speaker placement in our front room is not perfect for optimizing 2 channel stereo, as I suspect is true for most of us. But I do appreciate good sound even if I may not be sitting in the sweet spot. I have a line on a set of f206's for a decent discount from new, and folks who own them tend to like them. I guess I'll be taking the plunge.
Next on the list will be seeing how my 15yr old integrated drives them.

They are 88dB so no worries, couple hundred watts and you will be okay.

funny revel recommends 50-150w

Your 15 year old integrated - assuming it's a decent make and model in the first place -should be fine. Fifteen years ago was 2006; amplifier technology HAS changed in that time, of course, but unless you're going Class D or looking for streaming/HDMI options, a good amp fifteen years ago is going to be a good amp now, aging capacitors and/or tubes notwithstanding.

Revels are superbly made speakers. They'll sound great.

Revel are excellent speakers if you are worried about age I've seen the 226be under $5K.