I had a '10 FC 30' with the couch. In my infinite wisdom; the next year I changed the couch for the L-Lounge.
You lose room, as the long side is further into the coach (there's the storage cubby hole under the front window [made specifically and only for Tom's wife's yarn hobby
]) that takes up space.
The second thing is how uncomfortable it is to sit on; the padding is light and the shape is flat, creating an eventual slide off scenario. It's comfort is realized only when you're lying down on it.
The bonus with the L lounge is that you now have a real 2 person bed; which can also be looked at as a negative (if you're not looking for sleepover guests; sometimes easier to say, "I have no place for you to sleep" when you have the couch with a split level extended bed surface)
I'm now back to a sofa with my '15 Classic. I like it, but my dog misses his L-Lounge corner sleep spot
You can't please everyone.....