SL's have no problems with bad roads. When I was racing road, I beat those things hard at Harris Roubaix, and the only thing I needed to do after was change the bearings. Too much silt and rain and mud at that race. They accelerate really nicely up to speed, and climb beautifully because they are still plenty stiff for the weight, but have this empeccable ability to deflect road debris and remain comfortable.
The Elites would probably be fine for regular riding, but nothing feels like the SL' when you want to chase down a moving vehicle. Sudden acceleration is one thing I'll remember the SL's for. I had a set of Elites for backup wheels, and they didn't feel the same as the SL's. It's not just the looks that make them special!
Since you have to pay for them, see if you can borrow some for a ride and make up your mind that way. The only person that can decide if it is worth the extra green is you afterall.
When I return to the road next year, I'll be picking up a set of SL's for sure.
2005 Trek Session 77
2004 Specialized P3
2003 Giant TCR ONCE Team Road Bike