Is this a SIG P938 vs Kimber question? Or a SIG 1911 vs Kimber Solo?
Is a grip safety required? SA? Straight grip or round heel?
I'm throwing out some stuff because in compacts and smaller some features get left off, and the interpretation of "1911" gets fuzzy.
Be that as it may, you can get a dud from either. It would take longer to define and then test the two opponents, then purchase the winner than just buying the one you like and getting used to it.
The "which is best?" questions imply there's a clear cut answer and the alpha leaders on a forum will render their judgment in the next post. Well, if you search the internet, read the first few hundred web pages of 334,000, you'll get the idea nobody really much knows. It's a shifting target dependent on the quality of the line assembly workers at the time tested, vs who prefers what.
Most wind up picking the persona of the company they would like to have embellish their carry resume . . .
As for the extractor, you'll find guns that use both reliably.