Default Noob Question - Use any flash?

So this seems like a stupid question...but I need to ask it! As much as I'm used to installing custom roms and such I've not dealt with firmware before my Z1.

Now I think I'm on Eu generic right now (see picture). I was on EE branded...but EE tend to be slow...with everything, so it seemed logical to flash to something else.

One assumes it does make a difference to when you'll get the update? And that any flash will work fine as your phone is still locked to "X" network?

Sent from my C6903 using xda app-developers app
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