I somewhat agree....i also have been using Mi2 as only phone with no issues(spare the odd graphical glitch once in a while)..The only thing i was really saying is that if V5 is not 4.2 then it does not justify the version jump(from V4.1 to V5)....Anytime i heard about V5 i assumed it would bump up android version to latest. if not what was the point is what my mind was saying.... Android 4.2 brings new features(lock screen widgets is only one i can think of right now) and also improved security.
it is. i get it so seldomly that it's hard to pin point when it happens. it's been probably a week since the last time it happened. it seems to happen more when going landscape in some 3rp party apps to enter text then coming back to portrait....
So it is a software related issue... I've talked with Xiaomi support but they don't know what am I talking about, seems that I am the only person who reported that.