I'm going out on a limb here and following in the footsteps of JohnK by saying, you are seriously going to damage your hearing. Just how loud do you need to have playback in a room that small??
I pushed my M60s at one point years ago and hit 106dB at about 8-10 foot distance. The M80s can go louder, let alone with the M100s can do, and my room is quite a bit larger.
Honestly, i don't think you need to be concerned about the woofers bottoming out, not unless you are using a truly heavy weight amp for each channel. That Sherwood is good, but certainly should not be able to push those speakers into maximum excursion. I highly doubt it. If anything, pushing it that high is likely driving it into clipping.
Rated:
All-Channels-Driven Power 20 Hz-20kHz 100 Watts per channel (x 7) into 8 ohms 160 Watts per channel (x 7) into 4 ohms
These specs aren't much different than some high end AVRs.
If you aren't sure of the difference between max. excursion and clipping, hook up the Sherwood to just 2 smaller bookshelf speakers and then crank it up. You will know the noise of max excursion as the woofer hits with a solid thump/thunk sound and you will see how the driver pushes out and abruptly stops.
I've only seen this once before, using an Anthem amp (
http://www.anthemav.com/products-current/model=mca-30/page=specs) pushing two Tannoy Saturn S6s.
http://www.hifidatabase.com/Detailed/Tannoy_Saturn_S6_4871.php
