With status, there are four benefits to CE

* The free seat
* Food
* Extra miles and TP's
* D fares are often the cheapest flexible tickets on a route

Personally the only one of those that might make me buy up are the miles and TP's. I value legroom more than width so a exit row is far more desirable. Food - well I've wittered on enough about Plane Food - and on leisure travel I don't need flexibility.

However if you are deficient on the status front I can see the extras making a difference - lounge, priority check in especially.