Mobile Networks

Vodafone all the way.
Last year I did the 3 peaks with a mate.
He has always had voda, I was on o2.
He had a signal from the top of each peak & updated his facebook.
I could only get a signal from the top of Ben Nevis.
I moved to 3 late last year to get a sim only deal for my smartphone. Despite what their website says, the outdoor signal drops to nothing within yards of the main roads. I ended up buying a voda sim & shoving a few quid on it just so I could put live updates of our progress on my facebook.
Voda's payg sim only deals might not be anywhere near as cheap as 3s but their coverage is waaaaay better so I'm looking to make the change - I don't see why I should be held to ransom by 3, why should I choose a UK holiday destination based upon mobile phone reception?