My preference is, and always has been K frames.
The Job, however, has insisted on semis for about 20 years now. I believe strongly in only using guns with the same manual of arms, so I always carry Sigs. For fun, and hunting, and sometimes for pest control I get to use a K frame, but on the street, on my time or my department's time, it's a Sig. Wish it wasn't so, but oh, well. John