Tutorial [Q] the differences between z3x boxes

Hello guys

I want to ask you about the differences between >>

Z3x Box Bluemotion, Z3x Box Gold, Z3x Box, Z3x Box Gold

you can see which devices i mean by visiting "yaypel" website and chose z3x "sorry i can not but the URL "

I really need to know what are the differences because i'm gonna to buy one of them

but i cant decide which one is better

by the way, i need it to change the IMEI.

so, please if you any think about that just answer me and i will be very thankful