None of the colleges I was choosing between (Pomona, UChicago, Yale, and Northwestern) grant any meaningful credit for them whatsoever, nor did it knock out any gen-eds. They either granted a measly, couple "general elective credits" or "acceleration credits," which merely placed you into a higher level class where you could fulfill requirements instead of having to take an intro class. When they do grant a little credit here and there, you are bound by residency and minimum term obligations. This was a very rude awakening for my family, who is middle class, never attended college, and was under the impression that I was going to be able to graduate in 2.5-3 years with a double major and be on with my life.
That's on you for only considering those schools, isn't it? If you went to a state school, as most people do, you would be able to do just that. My abundant AP credit would have allowed me to graduate with a double major in three years, but instead I am graduating with a triple degree (B.A., B.A., B.S.) from a major public research university in four years. AP credit allowed me to skip introductory classes that would have bored me and allowed me to instead pursue more intellectually challenging coursework in a variety of disciplines beginning in my very first year. The cost of each AP test was also much lower than that of the corresponding college course would have been.
AP credits will probably not be useful if you are only interested in attending an Ivy League or similar private school. For the vast majority of students for whom that is not the case, they are quite helpful.
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