But also though, having multiple subs would cause sound waves to arrive at different times and affecting the sound that way too. Of course at the frequencies we are talking about, they are very much non-directional with cues such as directional "feeling". Some people are more sensitive than that.
Also for those of you using R&L, they may require 1 extra day to do residential deliveries. They load their truck early in the mornings for deliveries, before they even call to setup deliveries (for homes this is required) so I took off work today and no dice :/