The biggest difference for a career-minded individual is that they'll actually let you fly the damn thing. Reserve FOs fly, and aren't on reserve long -- this is a complete 180 from the other fleets, which have 9 mos-infinity reserve in the most junior bases right now and get sub 20 hours a month.

Besides that, there is also the issue of bases. DFW is available as a new hire in the 175, until very recently it has taken the better part of a year to get there on the 145.

The trips are also obviously much better. 5x 45 minute legs between the hub and nowhereville (overnight in a 2 star in nowhereville, 4 AM van out the next morning) vs. 1x 3.75 hour leg to an overnight in Mexico or something, cruise back at 2 PM to start your weekend. The CRJ is somewhere in between trip-wise, but again you won't get off reserve on that fleet until you get out of training as a 175 FO.