MichaelC[AP Moderator]
22395
My thoughts Seb
First and foremost, I always feel it is better to get the one your heart is committed to. If that is the 15500, then I would wait for it. That said...
IMO, the 37mm "looks" better than the 41mm in these 2 particular references. I have compared them side by side in the past and would choose the 37mm for myself. Maybe it is the length of the stick markers relative to the diameter. 3120 movement - have no fear about that. It is tried and trued. There were a couple of minor glitches that seemed to be production-batch related on the 3126 Offshore chronograph, but generally speaking, this movement has been an absolute workhorse for Audemars Piguet.
I wish you luck with your decision