I had the same debate - I've never ridden it, though. I did volunteer in both 2009 and 2013, and I thought that the route didn't hugely appeal as it's all familiar and I can ride the best bits at pretty much any time as I live in Darlington and my go-to ride is up Teesdale, so the best bit's on my doorstep, and the bits I don't know around London and Essex aren't places I desperately want to ride my bike (with apologies to the Essex lot!). I told loads of people that I wouldn't bother to ride it, usually after explaining that the price increase still represents bloody good value.
However, I had a change of heart, especially after riding the Mille Pennines, which was also all on familiar roads, but I enjoyed the event. It was a smaller field and a tougher ride, but I enjoyed seeing the roads through others' eyes, and meeting the same people, and I expect LEL to be even better as an event, and I'm looking forward to the atmosphere and the buzz of a big event on roads I already know and love.