I actually do pork side or back ribs for 36 hours at 145F. They're fall off the bone tender - the only reason that you cook them in the oven at temps above 345F afterwards is to caramelize the sugar in the BBQ sauce that you put on them.
(I use a darker sauce that has Guinness in it...the ribs get super-sticky and almost black in colour)
(I'm also a fan of using a UPS for longer cooks) The APC doesn't resume cooks if it looses power.
If you want to have a dry finish to them, you could just broil them for about 20 minutes to dry them out and crisp up the exterior a bit.