Not ridden one, though I have been in company of them.
Ben Lovejoy and dkmwt (forum members a while back) rode LEJOG on ICE trikes. I've met up with dkmwt - his name's Donald and lives in Plymouth - a few times and ridden with him a few times.
I met Ben and Donald at Launceston and rode to Okehampton with them along the OldA30 on their LEJOG. Long grinding hills, not steep, though they are long.
I was bored and cold as they were slow up the hills. Fast enough down them, but as soon as they came to one of the long hills, they slowed right down. I had to climb the hills at my own speed, ride back down, then ride with them again to the top just to keep warm and entertained.
They were nice and fast on the flat, and very fast downhill, but terribly slow climbing hills.viewtopic.php?f=24&t=14625
The slideshow is great!http://www.benlovejoy.com/cycle/tripreports/lejog/
Mick F. Cornwall