I'm really amazed at some of these posts...but I probably shouldn't be.
Go to 1. the company that gives you the first class date and barring that, 2. whatever company has a base closest to where you want to live.
At 0800 on September 11th, 2001 the "best regionals" would have been
AWAC
Comair
ACA
all others.
Today, the "best regionals" are probably
RAH
Skywest
Expressjet
all others.
I guarantee in two years that list will be different...so lets cut this circle-jerk kool-aid fest, shall we?