Without a doub’t the provider @joss uses, which I can’t think of the router they use at the moment. Your still using BT cables though with prety much the same speeds as you get now.
I’m with Virgin 350 and use my owner router (Archer AX73), I thinking of looking at one of the mobile providers come january as I’m going to ditch Virging TV box and going for either a recordable Freesat or freeview box 🙂