My comments are based on reviewers' measurements and owner experience with Energy speakers in general.
For instance....owners of the RC-Mini and RC-Mini at AVS have routinely states that Audyssey sets the crossover's for these speakers at 120-150Hz and 110-120Hz, respectively. This would suggest the rolloff is much higher than the stated specs, particularly for the RC-Mini.
Not only can I not imagine the lesser quality 3.5" woofer in the Take SAT giving further low-end extension than the 4.5" kevlar woofer of the RC-Mini when cabinet size is relatively the same.... but also take a look at the specs for the Take SAT. Energy lists the anechoic boundary (-10dB) at 75Hz. So the -3db @ 75Hz spec is not anechoic, but "typical" in-room response...and it would seem an optimistic spec at that. And, the -10db anechoic rating for the RC-Mini is actually lower at 70Hz.
It certainly isn't uncommon for manufacturers' specs to be optimistic...and while I am a big fan of Energy's RC-series...I still don't think the listed specs are necessarily accurate.
Also, many of the AVS owners are using the RC-Mini wall mounted (using the mounting bracket)... so even with rear wall bass reinforcement, Audyssey is still setting the xover to 120-150Hz.
BTW, I'm not sure I understand why you say you can't wall mount the RC-Mini. These speakers don't pump out alot of bass, so they have plenty of breathing room with the supplied wall mount bracket. Yes, they can't be put flat on the wall with a keyhole mount....but the advantage of the bracket is that it allows some flexibility in positioning/direction of the speaker, and doesn't limit it to flat on the wall placement.