I've just finished a 12 month stint with 4g broadband before returning to virgin this week.
My mast is three/ee shared. My EE mobile has clocked 283 Mb from this 4g mast so theories can work but generally won't. My three router sim would top out around 60Mb when I first joined them. But reality brought that down by half which isn't too bad considering what others write about on here. Peak usage might bring that as low as 10Mb.
Then three upgraded the mast to 4g+ and the router quickly enjoyed around 70Mb connections. I even bought a second router and that connected at 90Mb for all of a day and haven't seen that since.
But with three as all of us know the connection speed subsides within a few short hours. That 4g+ advantage I gained hasn't really been that advantageous. Connection speed and real life streaming speed are probably less than before the upgrade for me. Like others the CA doesn't always result in anything superior at all.
I gave 4g a shot, went for the cheap headline costs, yet probably spent even more on 'infrastructure' to try make it viable. The difference in virgin quality Internet this week for me is like a lada vs lambourghini.
Guess I should be offloading my routers and external antennae now