My nephew just finished up training there--he did 900 sims at Mesa AZ (Williams Gateway) but they were also sending about half the class to US Airways training center (at PHX Skyharbor), and for a few weeks they had him scheduled for Toronto/Bombardier, but they cancelled Toronto and moved him back to PHX.

He seemed to be pretty happy with the training department--I think he said they're trying to do IOE in the base you're going to, but it's mostly PHX & CLT for IOE.

Personally, if I was at his stage again (i.e. a new guy), I'd rather roll the dice at a small operation with a shot at a better contract and a significant relative increase in flying, versus going to a bloated/overbooked/very large pilot group like Republic.

Just my two cents--whether you want to live in Mesa's junior bases (or a short/easy commute away) is also a key factor. ymmv