I am in the process of enrolling at WGU, which, if you read their story, will probably be the leader of the pack of online educators in the next 10-15 years because of their innovation in education technology, and because of their extraordinary value (it's now cheaper than many state-supported universities).
While WGU and Aspen share many of the same accreditations, Aspen is not, however ... and I repeat NOT ... regionally accredited, which is the gold standard for academic excellence. You will hear people "rag" on WGU for it's competency units (as opposed to GPA), but it is still regionally accredited. Without that accreditation, you will not be able to transfer any hours to another college, nor will a lower level degree be accepted for admission to another grad school. This is an absolute standard across the board at higher institutes for learning.
Aspen makes no mention of this in the website, so who knows if they're even pursuing it or not ... but, without this, your degree is just a piece of paper with ink on it to another university.