The JVC wins for black levels, and I'll give it the edge in color accuracy, but more to the point, natural looking skin tones.
If you are doing a small dedicated theater, with, say a 92" diagonal screen, the Planar will really be in its element. Otherwise, overall, the JVC just overpowers or matches the Planar at most things except sharpness.
The Optoma HD8600 is a respectable DLP but still has dynamic iris issues. Optoma's been driving me crazy for years, with noisy or particularly noticeable iris action. A real improvement in iris action would elevate the HD8600 into a serious performer, even for this price range, but, again, it can't match the JVC for blacks, or color, but may have the slightest sharpness advantage - and again, not enough to matter, or so I think.