Ok, it's Evolution X, I know all about it. It is a custom rom, of course. My question was another: why isn't it good on board Zenfone 5? Very buggy? Lacking too many features? When I have some time, I'll try it personally. Bye😉
As I said, being a custom rom means it's nothing official (unless you mean official android, and not official asus release, which is the main point or most of the users nowadays). Evo x works quite well, except for banking apps and a couple of other issues. For me though banking apps are a must, so I had to go back to stock rom.