No change here, from last year's models. This JVC projector, too, leaks light out of the lens. This is especially true if you are using a lot of vertical lens shift. There's a bright side though.
That bright spot is that while the leak covers a wide area, it's so dark as to be a total non-issue. That leakage (which is outside of the projected image area) is no brighter - less bright, than the black levels themselves, and they are darker than with any other projector. If I was still in a room with an off-white wall surrounding the screen, I would be able to spot it with a virtually totally dark image projected, and the room otherwise fully darkened. In my current room where the wall behind the screen is dark, I couldn't see it at all.
JVC DLA-HD250 Image Noise
Nothing new here. For the 3rd generation, JVC has continued with higher end Silicon Optix for their image processing. They are still using the Silicon Optix Reon-VX (the lastest version no doubt). The Reon-VX is found in a number of excellent projectors. I'm not aware of any notable flaws in image processing. Mosquito noise is just visible, in normal amounts, without the Noise Reduction engaged. I don't see a need to implement it, but that is personal taste. Performance on motion artifacts is very good. As you can imagine, the HD250 like the other JVCs easily passes all the other related related tests that we use from the HQV test disc, as that widely used test disc is put out by Silicon Optix.
The HD250 does offer a contrast enhancement feature. As would be expected, it does slightly increase the image noise when engaged.