Grip shift is damn cool in that you can dump the cassette and just keep cranking. You cannot do that with triggers. However, that usually only happens when you get surprised on the trail. When you know what's coming, downshifting shouldn't be a problem with triggers.

Another cool thing is trimming out your front derailleur. Crosschain all you want!

I also accidentally shift sometimes with grip shifters when I'm trying to bunnyhop. It's less of a problem on the X9 and X0 because they only twist on your thumb & index finger, but the lower models I'd swear it is half the grip that twists.