They've all worked fine for me and I haven't seen much of a difference if any with the newest version. I was actually able to talk AT&T out of a microcell which took care of my only problem. House has insulated metal siding and I live in a little bit of a valley between towers.
They all suck for me. I`ve tried 4.4 all the way to 4.4.4. Only get 2mbps download no matter what even if i`m on HSPA+ or LTE. For some reason upload speeds on LTE will be at 10mbps and I don`t get it.
