External lever safety's are a deal-breaker for me on carry pistols.
Almost all pistols designed for carry are safely designed to where they don't "need" an external safety, and when milliseconds count, I don't want something that could cost me a half a second when I'm under duress.
The idea that a safety would prevent a pistol from "going off in the holster" is nonsense because NO pistol will "go off in a holster" if the holster is a proper one that encloses the trigger.
I've got XD's, an LCP, and a Rohrbaugh along with a few J-frame Smith's, and all are carried with chambers loaded with the only requirement to fire being that of pulling the trigger. I would not have it any other way with a carry gun, and especially when my wife has access to them. If she needs to use a pistol in defense and under duress, her mindset will be to only pull the trigger, not figure out how to "enable" the gun to fire.
So, for carry, no SR9c for me. I am however, considering the Kahr CM9 or CW9 (only difference being grip length and capacity) to add to my carry collection. They also do not have external safety's.
As far as the XD's for carry, they are thicker than any single stack, but if clothing allows, it's nice to have the extra capacity when possible.
For summer wear, it's usually the Rohrbaugh or LCP.