Have a look at this thread
http://rib.net/forum/showthread.php?t=19826
It's got a picture of the SR5.4 with 2x2 single jockey seats.
Works fine for us but we just want to go somewhere and not do much on the boat. It was also designed to be used by 2 x skinny athletic teenagers. I've enclosed another pic that shows a bit more of the layout.
As all to many others have said before me- work out what you want to do with the rib then work out how to do it. We wanted 4 seats, mostly only 2 would get used, 30knt performance and good seakeeping.
What are you planning to use it for ?