To me what really makes a pair is the magazine compatibility. I chose the glocks. Otherwise I don’t really see how it’s a pair.
I’d have a 34/19 combo, but for the choices a 17/26 is fine. Having another size between those is sort of redundant.
I carry a 19 most of the time, and a spare 17+2 magazine as well.
As an aside, I think the g48/43 would be a great combo if they shared magazines. Carry the 43 with a 7/8 round and have a spare 10 rounder with it. Unfortunately Glock missed that opportunity.