yes, if one gives you a UPT slot and the other doesn't go with the one that gives you the UPT slot.
Actually, all units are different. You'd have to talk to the guys that are there to see what they think. If lots of people are happy and like the unit then go there. If lots of guys are not so happy and are there because it is convenient to their family/airline job situation, then it may not be the place to be. We had several Ex-Reserve guys from 3 different units in my ANG unit and to a person they all said the ANG was better than the AFRC.
It is easier to change units in the Reserve because there is sort of an assignment system that can be worked. This is more of a player at the LT Col and above level when you start searching for command/leadership jobs. The ANG is usually not going to take an outsider or someone off active duty after the rank of major unless there are some very big extenuating circumstances IE that person is a school house instructor in a weapon system and everyone in the unit gives them a big thumbs up on the hire-o-meter!
From a part-timers perspective as a new guy completing flight school most guys would say the ANG version of the pay system is easier to get money in your pocket.