I do agree PIC time is very important, but I don't think it's the end-all. I would say look at the overall operation. If you took the SIC position, would you also get international? i.e. Canadian, Mexico, and Caribbean. Also Jet operations are slightly different than Prop ops. I believe there are "fair" regional jet operator's that have fast upgrade times.

I would also look at the stat's of current new-hires. Do most of them have RJ or prop PIC experience.

Ofcourse, in the end you have to do what's right for you.