I was just wondering if there would be any downside to getting the M80s over the M60s considering I have a smaller room ( 15*20*10)?

I am considering the relatively small increase in cost vs the futureproofing the M80s provide(for a larger HT room down the road)

Thanks again, in my first post here I couldn't believe how helpful everyone seems to be on these forums and sincerely appreciate the expertise you all so willingly provide.