I think you are probably right about me having the tower to myself, I doubt any other locals use mobile data, and in any case there are only a few hundred residents within 10 miles.
I had a strange thing this morning, my speed dropped suddenly to less than 3 Mbps and the bars dropped to 2 on the modem. I logged on to the Router and saw that I was receiving 4G not 3G. This lasted for about 30 minutes before reverting to 31 Mbps and 3g.
I Ordered a pair of Huawei antennae from Amazon, arriving tomorrow so I will see what effect they have,
The signal strength meter in the Router software has 5 bars, I have the full 5 bars, but perhaps the low power 4g signal can be improved, I think that the 3g was turned off at the tower for that short period so it reverted to the low 4g signal, If the antennae make a difference I think it will be worth going for the B525,.
While looking at the B525 on Amazon I noticed another higher model with a 600 Mbps capability.
I wonder if that gives an even stronger signal? A bit steep at £250 though Maybe the B525 and a good external antennae would be a better alternative and still be a bit cheaper.
Do you have an external antennae or are your slow speeds just due to network overload?