Man, this is an old thread
It's hard to say.
The PMR is generally like all the other PM's where it uses basically the same operated system save the lpr. In place of that, it uses it's Boost Forward Technology. The PMR has the trusted Hyper II Reg which you know will be great. The PMR has a lot of possible upgrades so you won't be lift with something stock.
However, the PMR has a very weak wiring harness, so you'll have to be very careful. It's also much louder than the OM line.
As for the SLG, there's not much i know of it other than it uses a sear to trip the valve. It uses the Hyper III reg, so they're not different regs you can put on yet. and the Marker is just as light as the PMR...
Hope it helps.