You have to remember that the flash isn’t entirely compatible with the camera. So you will miss some menu functions once you attach it to the body.
I tend to suggest getting an original brand speedlite. This is more expensive in the first place but will prevent you from buying the next cheaper one after the other until you have spend more money than you would by purchasing an original one in the first place.
Anyway, it will still be a good one in slave mode and you don’t have to get rid of it once you bought for a 580 EX II for example.