Really? Serious question – have you ever ridden down south?
I've ridden all over, and I've loved it all. South, North, West, Wales, Scotland (although not much up there).
I studied in London for a few years and did a fair bit of riding. Trails were uniformly pish, although I did like riding round the city itself.
I would sell the bikes, yeah, if it was London / SE commuterland. I'm speaking from the POV of someone who has to work to fit in cycling into a busy life. How could you justify going out for a weekend ride round Epping forest FFS? My missus would laugh in my face – you're taking 4 hours out of the weekend with me and the bairn to ride round that bag of pish? It just wouldn't work.