I have been using opera mini on my mobile for over a year and my personal experience has been great with this browser. I have never seen this browser crash on my mobile unlike chrome which crashes very often. I also has data saving option, which on extreme mode can save up to 90% data.
Browsing is very fast. Opens almost all types of websites. Very easy to use, all the setting options can be traced very easily. Tabs can be switched very easily.