If you take the 110's, the day will surely come when you will want the extra slam and muscle of the 210's for a room that size. If you don't, you will always feel like something is missing. You've already got too much invested in other parts of your rig to not fully realize capability of your system.
Do it now (210's) and save yourself the time and aggravation of upgrading later....as you surely will do if you buy the 110's.
Do it now (210's) and save yourself the time and aggravation of upgrading later....as you surely will do if you buy the 110's.