I pre-ordered the tegra note. First it is half the cost. Second, the tegra note has less latency stylus than the samsung (300 samples/sec vs 30 or 60) and variable tip width detection. This is because the t4 uses the 5th core to sample the screen. Third, the tegra note smokes the samsung in raw power and isn't weighed down by lag-inducing touch-wiz. Fourth, the HDR looks promising.
The only thing I can see where the samsung comes out ahead is the hover effect from the active digitizer, which seems a feabile victory.
As for the LG, it is a better tablet than the samsung, but you would need to purchase the stylus. The performance with a 1.7Ghz r9-based krait s600 and adreno 320 should be no match to the 1.8Ghz a15 T4, and it lacks HDR as well. It has a 1920 x 1200 display, but again the cost with a much less capable stylus is approaching $400.
Finally, I trust Nvidia to provide android updates over the others. My experience with the shield (now on 4.3) has been very good, whereas lg and samsung have been historically pretty bad at providing timely (or any!) updates.
An aside: The hp8 pro has a T4 chip and 1600x1200, but afaik no stylus. It will be interesting to see how that turns out. It might support a separately purchased stylus with the same capabilities as tegra note 7.