I'm a 3.
I have not run into major issues with the updates, however:
- Kobo has a tendency to make drastic changes to the user interface. Some people, understandably, get upset because it is no longer the product they bought. In my case, it leaves the impression that Kobo doesn't have much of a plan outlining the future of their products.
- Kobo pushes updates rather than letting customers decide if they want it. The only way to avoid these updates is to adjust your usage of the device or modify the device. (Adding to the fun, you can't predict when you're going to obtain an update so even the people who want the update are left jumping through hoops.)
- Kobo does not publish a list of fixed bugs. I understand why they don't publish a list of known bugs, but there would be a lot less confusion over whether to upgrade or not if a list of fixed bugs was provided.
- Kobo does not seem to fix a lot of bugs, even though some of those bugs should be trivial to fix. (Example: the PDF panning bug could be fixed by setting the refresh to 1 page within the PDF reader. It may be a kludge, but it will keep people happy and should only involve one line of code.)
- Kobo has yet to implement the "vaporize user who complains about Kobo's updates" feature, even though it would increase the sanity of posts of Kobo forums.