R H Clark has it right. Much of decision will be personal. I shoot the PSA and can't put it down. I like a 60" bow for hunting and the PSA's riser is shorter which allows me longer working limbs.
I'd try both and find the model that fells better to you. Personallly I shot the PMA and did not shoot it well. For me the PSA just fits.
Too, I have had excellent customer service from the company--especially from Ken Beck at a PBS banquet: I won a PSA (my first Blackwidow) at an auction and went to his booth for advice on setting the bow up: brace height...et cetera. The bow I won did not have a string, and Ken did not have one in his booth, so he took a string off one of his demo bows. He pulled out a bow square and busied himself setting the nock point, brace height, handed me a owner's manual, gave me a lesson on tuning, and installed a limb-tip protector. Expecting to just pick up a string, I'm like , "Wow, Thanks!" and I pulled out my wallet to pay him, to which he answered "Don't worry about it. Enjoy the bow".
Ken's service sold me on the company. My PSA sold me on the bow.