No Dynamic Iris
JVC's exceptional blacks are due, first and foremost to their LCoS panel design. They simply created a panel that has higher native contrast than the panels coming from Sony or Canon. The JVC X70 produces the blackest blacks of any projector I've worked with. (That is, other than a CRT in the "old days".) Because the black levels are achieved without a dynamic iris, medium and brighter scenes, still have exceptionally black blacks. By comparison, other projectors blacks would have to lighten as the iris can't close down all the way. If the iris did, it would dim the bright material, which is undesirable.
3D Abilities
This JVC X70 is definitely capable of 3D, but 3D is not its strong suit. The 3D is certainly very watchable, but it has some issues. There's more crosstalk it seems than most other projectors. It's often more apparent than with competing projectors, like the Epson and Sony. There's not a lot of lumens under the hood of this JVC for 3D, with 3D gobbling up about 75% of brightness.
I watched a large chunk of Hugo, and a several segments from Tron, Ultimate Wave Tahiti 3D, etc. Projecting a 96" diagonal image onto my Studiotek 130 (1.3 gain), I felt there wasn't quite enough lumens (and that's with a virtually new lamp). The bright highlights on the racers in Tron Legacy weren't the eye catching "Bright" I expect. Same for Jeff Bridges home with its diffused white lighting. The roon never felt bright enough. Hugo wasn't bad, brightness wise. Again, though nothing is ever really bright. Don't get me wrong, it's easy enough to still enjoy a movie. If you're really serious about 3D, and don't want to be on the dim side of 3D, there are now several projectors that are twice as bright, and that's a big difference.
If you are really serious about 3D, this JVC isn't going to be your best choice. If , on the other hand, 2D's what you care about, but will want to play with occasional 3D, or if the kids want to watch in 3D, thie JVC X70R should serve you beautifully.
Let's say that the 3D is good for the occasional viewing.