You don't say what model Coach you are looking at, or if the new L shaped sofa is a Newmar standard or aftermarket, so not a lot to go on here.
I will say we have the stock L sofa ( Newmar ) in our Ventana. Its OK as a sofa / absolutely terrible as a bed. Kids don't even want to sleep on it. Newmar purchasing agents should be forced to spend a night on it !
2014 Newmar Ventana 4037 / 4018
2015 Jeep Grand Cherokee Ltd.
1940 Chevrolet Pickup