For people on Kobo: Koreader handles standard epub way better than the native reader.
If you've ever tried reading an epub using Kobo that you didn't buy from the Kobo store, you may have noticed that highlighting text is very laggy. Koreader has no such lag.
I believe Calibre (very) recently added a feature to make conversion to kepub automatic when transferring to a Kobo, so things may have changed on the ease of use front.
If you've ever tried reading an epub using Kobo that you didn't buy from the Kobo store, you may have noticed that highlighting text is very laggy. Koreader has no such lag.