CRJ reserve time is pretty much like upgrade time at Eagle. Don't try and do the math, just pray something happens and try not to think about it in the mean time. If you REALLY want to get a line ASAP, pick BOS on your first day of training and put in a bid for ORD on your second day. You get an EMJ slot in class (all we got in Boston) and you will be transfered to ORD possibly before IOE and you will get a line rather quickly thereafter.
AVOID the CRJ unless you live in your base and don't really like working. I flew 6 days and credited less than 12 hours for the month of January. I spent more time banging my head against the head in Chicago than anywhere else. If I were on the EMJ (if I had gone to BOS and xfered), I would have a commutable like with desirable flying.
The 700 may be a better airplane than the 145 in my opinion, but Eagle doesn't have enough 700s to know what to do with them or where to fly them.