UPDATED 11/13/15 with real-time videos. See below.
Thanks to Mashable and Lance Ulanoff's review of the iPad Pro this morning, I discovered this very easy way to capture lag, using my iPhone 6's Slo-Mo feature.
In all four of the applications below, lag is nearly imperceptible in real time. And in each, once captured at 240 fps, the delay is nearly identical while I draw at my typical light pressure. The earlier video I posted showed how bad lag can be in Photoshop if a lot of pressure is applied.
In Ulanoff's test video, the Apple Pencil and iPad Pro delivered slightly less delay, but his Surface Pro 4 strokes were broken up and inconsistent. I have no idea what software he was using on his SP4. To reiterate, in real time at the speed at which I'm drawing these loops, the lag is imperceptible to me.
I may go back to other devices and see if the lag is better or worse. I'm definitely curious to know how much better or worse the Wacom EMR on my Lenovo Thinkpad Yoga 14 performs. What do you think?
UPDATE 11/13/15 Several of you requested real-time videos. The first one below is in Sketchook Pro and the second is in Clip Studio Paint.