I have seen a number of 1st gens with the 5.1 update but none for me yet.
I purchased mine from pbtech, dual sim. Works well but in NZ but mod probably not supported by nz carriers. Is there any way to figure that out for sure?
Cheapest Online Bookstore Free Worldwide Delivery
MOBILE: Nexus 6 & HTC U Play
TABLET: Ipad 2017
OTHER: Asus Vivobook + Intel NUC5i3 + A family of Raspberry Pi x 9 + Amazon Echo