While I did look at Klipsch extensively, to outperform BMRs significantly it would have blown my budget by too much. If you're talking RP160s all around...that's the decision I tasked myself with and went with the BMRs all around with MTM center.
I think you made a great choice going with the BMRs instead of Klipsch sold at Bestbuy.
Could you define "reference volume" please? Seems to be varying definitions searching online.
Listening position is just under 3 meters from fronts and LR surrounds. Rears could be up to 6 meters at back wall or if side-wall mounted and angled towards listening position then 3 meters is doable (not sure if that's a good way to mount). The link you gave for SPL Calculator puts me just in range without an amp if I understood it correctly. That does beg the question regarding "dynamic headroom" though.
Thanks...definitely looking for more suggestions on subs as I have no clue what I'm doing...on any of this actually.
Unless you are really keen on listening to THX reference spl (85 dB average) from more than 3 meters you should be fine, though I would still strong suggest you can an amp for the BMRs.
6 meter for the surround speakers does seem too much, try to get it closer to 3 meters or 4 if you must, and then crossover them at 100 Hz or higher should help, and that's another reason to go with the best subwoofer you can afford.