here's the thing: if you use standard length clubs, the bag will fit...without your woods and driver. i have to say that this is the single item i feel i was misled with regard to, through the course of my purchase. the salesman at the first place i looked at the C says, when i ask if a bag of clubs will fit in the trunk: "of course. it's a merCEDes, after all..."
so here's what i do: i fold down one seat to accomodate the longer clubs and just suck it up. doesn't thrill me, but there it is. when i go to the driving range and am only going to hit irons, though, the seat can stay up.
come on...get the car anyway. you'll be glad.