I use two of my bundled reverbs 90% of the time. When I get bored or feel lazy, I can always dig out one of the 3rd party ones. Valhalla is a long time favorite of mine.
So is IK's CSR, which is as close as it gets to instant gratification this side of Lexicon. In fact, CSR is probably the first thing I try if I venture down the 3rd party plugs menu. I rarely have to go any further.
I do love my Lexicon but I haven't connected my iLok in months now.
The Sonitus plugs in Sonar have always been underrated.