It looks tighter in the photo than it actually is because its a wide angle lens on that image. But basically you sit in the forward facing seats and stick your legs in the middle with the table removed, definitely enough space for a couple of kids not sure how adults would get on with it I haven't tried yet!
The conversion was done by Cascade who are the only ones I've seen who can do a U-shaped layout with seatbelts, apparently they have a patent on their system. Definitely works better for what we wanted than a standard side conversion with R&R bed, I'm really happy with it