Josh, the most common suggestion is probably that the front speakers(i.e., the drivers, not the enclosure)should be separated about as much as your sitting distance from them, and this is how my M22s are set up. However, others are of the view that if the seats are as much as 1 1/2 times the separation distance away, this is still fine.
I'd suggest that you use the wider spread that you proposed, even if they're then close to the side walls. Being quite close to one of the room surfaces(floor or wall)isn't necessarily harmful if the distances to the other two surfaces differ. The distance from the center of the woofer cones to the floor and two walls should all be different so that the room boundary effects don't tend to pile up at the same frequencies, increasing the peaks and dips in the upper bass/lower mid-range.
