Where are you going to be sitting in your room? You won't line up everyone along the back wall will you?
If you are really concerned with room acoustics, and I think you are as this is your second post, I suggest reading Doug Self's site if you are not already familiar with it. Long discussions on this topic and a very interesting site.
I have heard the Studio and if powered well it is up to your room. It may sound different. A room 18 by 18 is going to reinforce soundwaves (room resonance) slightly below 30hz if the room was typical. Your room will not.
In addition, there is a lot you can do to tweak a room. Your room is not to large and frankly has better listening dimenions that the audition room. The wall material and furniture, floor covering, will have more to do with the sound than the dimensions. Where you sit will be especially important. Does the room give you a good choice as to where you will sit? If so, you should't worry. Again, go to Self's site for a long discussion about this.
I think you have made a nice choice on your speakers. Very nice really. Enjoy!!!
Sincerely, I remain