Chances are you'll go directly to the jet if hired at MESA. Anybody who is in the 1000 + flight time with some sort of real world experience ususally goes to Air Midwest in the 1900's. That is where I'm at and I wouldn't trade it for the dark side.
You're going to take some flak over this. I know were you are at though. I tried a similar program that went tits up and ended up flight instructing and flying freight for a couple of years. I am really glad I did but I would not of known any different if I hadn't.
What ever you do stay away from Gulfstream they are flat out selling a seat in an airliner. ATP has a good program but it is nothing different than the Mesa thing except for the contacts for the guarenteed interview.
Good Luck