Due to line contention / crosstalk, my 4G connection is now faster than my continuously degrading home VDSL2 connection (BT's "super fast broadband" fibre-to-the-cabinet offering).
However, it still doesn't mean a huge amount because data caps here in the UK seem pretty restrictive. It costs a small fortune to get a data package that might start to give you a landline-replacement service: A 20GB package is probably going to be £40 a month or more.