I've flown VY a few times, mainly on short sectors to/from BCN, and found them ok. The legroom is a bit grim, even though I'm not that tall, and for that reason I wouldn't really fancy them on more than a 90 minute or so sector, but otherwise no complaints. Not had IRROPS so far though (mind you, it's not as if some more vaunted airlines distinguish themselves in tha area).
"Worst airline ever" is just the usual internet hyperbole, we live in an era when people struggle to just say "it wasn't very good" when they have a poor experience...