Well, you are correct in that not all AFReserve units will accept applications from people not qualified. My opinion on the matter is that the ANG is state funded and could be more likely to run out of funds by the end of the fiscal year. However, ANGReserve or AFReserve, they are both great career tracks. If Pitot Heat is going to be starting college soon he should definitely look into ROTC on the college campus. That'll allow him/her to experience military "protocal" with no committment. Only in the junior year do you have to sign on the dotted line.
AFReserve is identical to the ANG in that you are garunteed your airframe once passing basic flight training. Just remember though, seniority is key. Getting furloughed at your airline dream job may be the difference between two weeks of date of hire.