1. Don't know, since it isn't out yet. If it's anything like the original, it'll be good for everything but GBA games. 2. Great if you don't mind the lack of homebrew support. Apparently, it has to do with Team EZFlash refusing to release the write code to homebrew programmers. The only person that has it is Infantile Paralysiser (creator of Moonshell). 3. Great if you don't mind the amount of space. If I recall, mr hanky once posted that the chinese isn't too hard to get around on the M3, so it's probably the same with the G6.
Yeah, I have a chinese G6 and there is only one menu I don't understand, i've worked out it has something to do with the save files, howwver everything works fine without me having to use that menu, so it must be for if you use multiple saves or something.