Robie, what type of music do you generally listen too with the 4's? I think allot of times, we all like the sound of different speakers, because for the most part we all listen to different music, and we also all hear things differently.
I once had a friend over, who thought the 3's were the best sounding speaker I own. This was before I had the ones. To me the 1's and 3's sound exactly alike.... (and I really mean absolutely identical), I would bet your 4's sound very similar to mine, due to the same drivers being used.
One thing that is interesting is the 1's came with a equalizer, much like a Bose 901. I do not have this equalizer, but I suspect it would modify frequencies similar, throughout the entire model lineup.