I have very recently had to make this choice, so here goes:
CSL is clearly a more special car and not a car you see everywhere - the shooting break especially is quite something.
However, I went with a facelift (2014) E63 wagon against a similarly priced CSL 63 SB for the toys: 360 degrees camera, B&O and alcantara headliner. 360 camera only came in on the facelift CSL and the other options seemed rare on a CSL. The E had its facelift 2 years before the CSL. Finally, and this was just my need, my garage is 5 metres so with a CSL SB it simply wouldn't fit, whereas the E is about 10 centimetres shorter (4.91).