Three network struggles more indoors than other networks due to the frequency used for 3G. With my iPhone 4 on 3 I don't get a signal in shopping centres or Sainsburys (Greater London, Uxbridge) because my area is covered by 3G Three have turned off Orange 2G roaming as well. So it's 3G or No Service
100% depends on the signal and services available in your area.
This. This. This. THIS.
It totally depends on where you are, even down to small areas too.
How people still don't understand this is beyond me.
2G roaming exists where there was not enough coverage for 3 to use just their stuff alone.
Three network struggles more indoors than other networks due to the frequency used for 3G. With my iPhone 4 on 3 I don't get a signal in shopping centres or Sainsburys (Greater London, Uxbridge) because my area is covered by 3G Three have turned off Orange 2G roaming as well. So it's 3G or No Service
Sorry to resurrect this but that's not true; O2 have been allowed to use 900MHz for deploying 3G for some time now.To make it perfectly clear, 3G is on the same band for all networks, 2100Mhz, if anything Three have one of the largest deployments of HSPA+ going for them. 2G roaming exists where there was not enough coverage for 3 to use just their stuff alone. Shopping centres have repeaters in which all networks use equally due to density so I wouldn't consider this a huge issue, all networks suffer in the same way.