So my question is has anyone here done this and how did go?....
I've finished four 210 ATBs on the trike, first three Melb - Sorrento - Queenscliff - Melb, last year Melb - Sorrento - Melb.
If you have a few trike km in your legs, then the 100 km ride will be a doddle. The long ride comfort of recumbents generally, and trikes in particular is one of the payoffs for the toting the extra weight. When the bike riders are lifting off their seats to ease that numb-bum feeling, you're still relaxing in your banana lounge!
All I'd say is to prepare with a few longer rides leading up to ATB and drink / eat heaps on the day.
What trike are you riding?