If there is much benefit or not is for you to decide. There will be differences, if the differences are worth the extra $$$ is up to you. FYI, I have M80s in a room smaller than what you describe (my living room is 20*11) and love them. A few people on this forum have done a direct comparison, I am sure they will chime in.

Bruno
M80s/VP180/QS8s/EP600/AVR-890
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"The problem is choice..."