A Galaxy s6 with edge firmware D: !!!

Hi guys!

This is my story
I bought a Galaxy s6 today in japan akihabara, a "sim free" phone..., I was checking the phone at a restaurant and I found that this cell have a edge firmware o.O
The number model is: SM-G9250
but the real model is: SC-05G

At the moment works fine, but I would like to root it with a real S6 firmware, not a edge firmware...
Do you have any information which firmware can I use? I need it sim free.

Thanks!! :D:D:D

pd: I don't want a iphone, please help :'(