I had used Kobo Glo in the past for a few months, and given up on it

. I am now a Kindle user. I should admit that Kobo Glo HD has caught my attention. Being a Kobo Glo user in the past who wants to give Kobo an another try I would like to get your opinions on the following
1) Is the firmware still buggy?
2) How easy to install koreader on Kobo Glo HD, as I would like koreader to be the main reader on the Glo HD.
3) Is the screen lighting even? I am not happy with the Kindle Voyage frontlight after a few replacements.
4) Does Kobo firmware gather the highlights in a single text file as Kindle firmware does?