Nice prices. You're apparently a better hot-dealer than I.
What voltages were you trying, for 3800 and 3900? I was able to just dial-in 3800 and 1.350V easy-peasy on my two R3 1200 CPUs, but the one that I tried to push to 3900, didn't want to go. I didn't try the other one.
Yeah. So many people (Intel fans?) put down the R3 1200, because of it's anemic 3.1Ghz base-clock speed, but overlook the fact that it's overclockable (if you use something better than an A320-chipset board) to 3.8Ghz really easily, using the stock cooler included in the box (no expensive cooler to buy).
In many ways, it's like AMD's G3258. (Although, in other ways, it's not exactly like that.)
It's quite a budget bargain, and in my testing, outperforms the G4560 in both ST and MT, once clocked at 3.8Ghz or above.
Edit: To add, I look forward to testing the R3 1200's competition, the i3-8100 and i3-8350K, in the next few months.