K..finally I've received my G6 lite and Passcard 3 this morning and wanted to clear up some points here. The G6 lite received has a CHINESE interface and I did flash it with the V4.0c English version from the website...turned out my G6 wouldn't boot up with it until being reflashed again with Chinese version. I was a bit disappointed by the fact of this but...honestly, after playing with it for a while, the Chinese interface wouldn't bother you as you thought it would because all of the games are named English plus I don't think anyone would want to use Nintendo DS for other stuff like PDA. Oh and last thing, GBA mode is in English for sure.
Edit: one more thing, the clear crystal white coating of the top cover doesn't appear on G6 lite...it's got a white painting and that's it.