I started with a Mu P8. SL is 8.7kg without pedals. FWIW my 12+kg bike was listed as 11kg on the Dahon site. My heavy pedals (with power grips) should be just about equivalent to the stock folding pedals.

The important light bits on the SL vs P8 are:
- Kojak vs Marathon Racer (-200g) and lighter innertube
- FSA Gossamer crank vs Sugino XD - has anyone weighted their XD and BB?
- Kinetix Pro wheels vs Kinetix Comp - again, does anyone have stats on this?
- SRAM X9 vs Dahon Neos - should be substantially lighter.