The SLR 101 has been re-branded as the SAM7. Apparently the current batch of SAM7 are the exact same as the SLR101s you could buy last year. Milled bulgy.
I'm not the most knowledgeable guy on here, but the SLR101 is the nicest I have experience with. Better trigger pull from the factory. For me, I'm more accurate with irons with the SLR101 than a LE6920.
There is a lot of buzz right now about the SLR107. Plenty of testimonials that it is "the best AK, with the smartest configuration, ever." Maybe. It also happens to be the model Arsenal is shipping right now. It is also some $400 cheaper than the SAM7. For that $400 you get a milled receiver, better trigger, and maybe a tad more pride in ownership.
Eighteen months ago, the SLR101 was selling at the same price that the SLR107 is going for now. In another 18 months, I'd be surprised if the SLR107 isn't up to $1400.
Practically speaking, both are excellent. The SAM7 is a bit more polished NIB. The SLR107 may require some trigger work. Either one, IMO, is a top-rate choice as a primary SHTF (or what have you) rifle.