See, the problem I find with comparing Systema and NGRS, is that whilst they're both trying to provide a premium product that has greater realism, they essentially do that in entirely distinct ways. The NGRS's main selling point is in the name: Recoil. Whilst they do provide a more authentic sense of weapon manipulation, they are still at their heart a TM standard aeg with all the foibles and benefits that system presents. Systemas/PTWs are built as a simulator that happens to fire bbs. Theyre designed to be thrown around in a training scenario with military/le users, and focus much more on compatibility with real steel accessories. The fact they work as well as they do is a side effect of Systema's manufacturing prowess.
All this to say that there isnt really a superior platform. TMs may not have the compatibility perks, but they are far more accessible in terms of parts and transferable teching skills, whilst PTWs will never have the depth and breadth of parts support, but arguably don't even require it as with only slightly more advanced teching skills they can feasibly last longer than most standard v2/3 based rifs with stock internals.
I'm definitely biased, but that doesn't mean I don't see the good points of NGRS. It does feel however, that at the point most of them have been modified to a players tastes, you could have just gotten a PTW and all you really lose is "Recoil".
always been fascinated by them but never justified the price of one. Really niche which I kinda dig 
