Originally Posted by lost boy:
“It is indeed.
In your case you're probably right. IMO I'd say you're getting 3G900 from O2 and 3G2100 from Three/EE, which would explain the difference there and, as long as Three put out their 800 at similar power levels to O2's 3G900 you should be fine.
In my case (just for comparison) it's all a bit of a mess, and I probably know far too much about it for my own good:
My nearest O2 mast and my nearest Three/EE mast are both pretty close to me, and about 100 metres or so away from each other. O2 is 2G only though (circa -89dBm) while the Three/EE mast is hopelessly congested so won't accept connections except for overnight in the small hours (at circa -83dBm on 3G).
Second choice Three/EE mast is a bit further away (and is, I believe, the nearest one EE have 4G on), but gives -89dBm or so on 3G (about the same on 2G). Second choice O2 mast meanwhile is further away still, covers a sizably large area, and gives -105dBm or so on 3G2100, -87dBm or so on 2G900... and around -89dBm on 3G900. However, due to poor mast location and lack of masts, cell breathing is very much in effect and that 3G900 signal is anything but consistent, which is a bit of a shame really as when available it's actually very good.”
I should have mentioned, O2 and Vodafone are stuck on EDGE/GPRS indoors so 2G900.
Vodafone seems to have 1 or 2 bars of HSPA+ outdoors now (-105dBm signal at maximum) but the connection doesn't actually work for anything. O2 3G is nowehere to be seen.
4G is now available from O2 and Vodafone, with identical signal, but at -120dBm so I'm guessing that's a shared mast but quite some distance away.