Good point... I didn't think about the differing distances to each speaker!
I'm thinking about getting 5 of the O-3's for my 5 channel HT and then getting a couple OB-5's after upgrading to 7.1. Initially all would be crossed over to the sub at 80Hz (non-adjustable crossover... so it's either cut 'em off there or the run 'em full range). After upgrading to a new 7.1 pre/pro or receiver I'm sure I'll have better bass management at my disposal.