I thought Good Ereader's video comparison review of the Kobo Glo vs. the Kindle Paperwhite and (the oldest model) Nook Simple Touch with Glowlight was very fair. I think it is significant that the review was conducted in darkness with the three glowing displays next to each other, but they kept the Glo on at full brightness nearly the whole 15 minutes. Personally, as I don't watch TV in total darkness, I'd have difficulty using any lighted display in darkness.
The reviewers were very happy with the Paperwhite's pinch-and-zooming on PDFs, but noted that the Glo was tops for graphic novels and still pretty good on academic PDFs.
They noted that Kobo is the friendliest to sideloaded ebooks but knocked the Glo on the lack of control over margins and linespacing. I agree as that is what I have found on the Kobo Touch, and would put improvements in sideloading at the top of my request list.
BTW the reviewers panned the Nook model and wondered if B&N was giving up on eInk. This seems to be a meme but is it correct?