I've compared the AP2 and the old Off Ramp 3 with a BPT power supply. No contest, the Off Ramp 3 was the clear winner. And the Off Ramp 4 and 5 are supposed to be marked improvements over the Off Ramp 3.
Having said that, when I owned the AP2, there was no battery option. Probably worth trying.
Having said that, when I owned the AP2, there was no battery option. Probably worth trying.