I found a few big cons in Opera for me, this was the reason, why I deinstalled it:
- Can't clear browsing data on exit.
- Can't create apps for websites like in edge.
- Browser doesn't close when the last tab is closed, and there is no option for it.
- Lack of customizability. (Like move around objects everywhere and change anything how you like it)
- Too round interface.
What I found good (in comparison to Edge): - Not mandatory synchronization.
- No edge's red dot of doom.
- Flow.
- Free VPN, but it would be good if we had a button for it on the search bar or side bar.
Though your browser is better than edge on android, I didn't find any big cons, so I still stay with opera on my phone.