It's not as bad as the legiondaries, but the disappointment is just as crippling when you get a bad corruption or none at all on something that then fails to be an upgrade.I think this comparison fails a bit due to the timeframe between corruption drops being much, much shorter than legiondaries. You can get multiple corrupted items a day.
I do actually still like the core idea of the system at least, it just feels like something that an expansion should've been built around rather than slap it all into a patch.