Russia’s S400 is rated #1 air defense system on the planet by numerous military publications and sites. There may be some disagreement here and there about first place, but they undoubtedly have one of the world’s best ADFs.
I don’t know or really care about what Air Defense System is the best except that Russia has capable systems.
They will be shooting at F-16s flown by inexperienced pilots who will get shot down in short order assuming Ukraine actually sends them into battle.