> they didn't provide a good hardware solution for 4G. That's right, my street doesn't have fibre despite being in the tech startup heart of London. So here I am with a TP-Link router.

Same situation, another UK city center, without fiber, and with an incredibly noisy, effectively useless 1Mbit ADSL line.

I really wanted something running an open firmware, but for LTE you really need something >= Cat10 for reliable home broadband, and there isn't a lot of choice at this end excluding crazy expensive commercial stuff - It's either Netgear or Huawie. After learning way too much about LTE, I ultimately settled on a Netgear M2 (MR2100) and a couple of magnetic MIMO antennas out the window, which has worked very well, and the firmware isn't terrible. I was initially repelled by the high price ~£400, but you really need the 5x carrier aggregation of Cat10 to get something reliable, the cheapo Cat4/6 TP link stuff is not worth the time IMO.

[edit]

At the time there was one industrial LTE router manufacturer that caught my eye "Teltonika" which ship with OpenWRT as the official firmware! but at the time they only had a Cat6 modem. They now appear to have added a Cat12 one! "RUTX12 and it's price is not dissimilar to the Netgear M2:

https://teltonika-networks.com/product/rutx14/

If I was buying again id give this a shot.