I just got my R-9S last week, and cleaned then reassembled it with just my fingers, but inserting the recoil spring assembly was nowhere near as easy as such things are with Glocks, HKs, Kahrs and Sigs.
I eventually got it, but it took minutes instead of seconds, and I believe I'll pick up a pair of 10" Channel Lock pliers at Ace today.
It's not a gun to be quickly and easily "field stripped!"
Such is the price of having as teensy a little 9mm pistol as possible, with no external protruberances, I guess.