Russian engines not good?
Well, even the ancient, crude built, tumansky engines on the Fulcrum can operate flawlessly at angles of attack the F100&F110 never have been nor will be. The bigger AL-31 are working even with the Flanker flying tail first and without any FADEC control. Surely the MTBO (Max Time Between Overhauls) is 50% worst than the American counterparts but that's due to different philosophy. Once, Tupolev and C.L. Johnson were having dinner and Tupolev said to him "You Americans make airplanes like a Rolex, you drop it and it stops" (From B. Rich "Skunk Works")
The Mig 25's engines R-31, if operated at speeds>Mach 3, they tend to overheat and finally destroyed. This is because the combination of the high rotational speed of the compressor rotors and the flight speed. The result is tremendous temperatures that will melt the metallic parts. They have short life parts, but they are cheap to make. The DF30 of MIG-31 are very efficient. I don't know any other turbofan that can work from 0 - 3.1 Mach.