I'd agree with intheair10 to a certain extent. Turbine time is turbine time depending on where you want to go. I believe SWA min quals require 1000 PIC jet, thus you'd need to find a jet to command. Most other places don’t list the jet time as a min qual however (last I checked anyway). I have MANY friends who got hired at AirTran and they ALL had nothing but turboprop time and most from RegionsAir. I also have a couple friends that got hired at UPS with nothing but turbo prop PIC time, but that has been 6 months to two years ago so it might have changed.
My point is really, that it all depends on where you ultimately want to go. If you are just looking to get on with a stable (and I emphasize the word stable) airline for your career airline I’d go with a quick upgrade type place such as Regions. However, if you are targeting an airline that specifically requires the JET PIC I'd go with some type of fractional or corporate jet gig. Going to most regional airlines with jets now-a-days will require probably a minimum of two to four years sitting the dummy seat, and that is a long time of passing up opportunities to go to better airline jobs. Those jobs fill up quick (there are A LOT of qualified pilots out there) and the longer it takes to become qualified for those jobs the less of them I think you will see. Also, my take on regional airlines is that they are ALL like a pair of shoes worn by the Major airline that buys them. Once the shoe no longer serves its purpose and is used up, they (the Majors) move on to the next "discounted" pair of shoes. So the argument of picking a "stable" regional airline to use as a worst case place to end up and make a career out of is not a good one in my humble opinion.
I'd also agree with intheair10 about flying a turbo prop like the JetStream making you a better pilot. I've flown both J31/32 and EMB135/140/145 RJ and I definitely would tell you that the prop made me a much better stick. You can't make a pitch or power change in that thing (JetStream) without having to retrim, and anyone who says that have made more that three greaser landings in a row in that thing is a liar
I also flew the ATR before swapping into the EMB and while the ATR is a pretty easy plane to fly it was way more challenging than the EMB. The EMB is easy and relatively nice if that’s what you are looking for, but I will say this about the EMB - you get what you pay for (from an airline company's perspective).
In short, evaluate your goals and decide what you ultimately want (which airlines you'd like to target as your career job), and do what you need to do in order to meet those particular job requirements.