The 4" 686+ weighs 38.9 oz while the 4" 627 Pro weighs 41.2 oz - that's 2.3 oz - hardly a huge increase. Yes, the frame and cylinder - of necessity - are slightly thicker. The benefits of a spring-loaded front sight, being moonclip-ready, and the x8 capacity are significant.
The 2.5" 686+ weighs 34.1 oz while the similar sized 2 5/8" PC627 UDR weighs 37.6 oz - 3.5 oz more. It is a Performance Center revolver - with several improvements over a production variant. I had a 5" PC627 Jerry Miculek V-Comp - super revolver - but huge looking and feeling. I sold it to fund a second 2 5/8" PC627 UDR - a real sweet shooter.
While I 24/7 carry pocketable CCWs, like my 642, 632 Pro, 351PD, and 296, I do have holsters for my 627 Pro and a PC627 UDR. I carry them very infrequently... the 642 is most commonly found in my pocket.
Stainz