I own a Scorpion Carbine and more recently a Ruger PC Carbine
Just wanted to share how much better the Scorpion was designed for field maintenance. Basically all you have to do is slide out one retained pin to get to the entire action.
The Ruger PC Carbine is a nightmare compared to this. You need a hex key, inch / pound torque wrench, push out multiple loose pins, and lord forbid that the recoil spring retainer doesn't go flying off like mine just did when removing the bolt.
I do like the use of Glock mags though in the Ruger, but would never want to maintain it out in field conditions.