I'm guessing the SL has a CHADEMO port for DCQC, does the SV?
If the 2014 SV has the LED + charge package, that would be ideal and much closer to an SL with respect to important features. If it also has the premium package, with the Around View cameras and Bose speaker system, then that would be a nice bonus. My wife wishes that our SV included the backup camera, but it wasn't a deal breaker for me given the price we paid.
If instead the SV has no extra options (i.e. no CHADEMO, no backup camera, no Around View), then I would personally buy the 2013 SL at $9000.
Having said all that, the health of the traction battery is paramount so if the 2014 SV has a significantly better pack then buy that one.
Vancouver, CA owner of a 2013 Ocean Blue SV + QC, purchased 01/2017 in WA
Zencar 12/20/24/30A L1/L2 portable EVSE
1-1/4" Curt #11396 hitch
After market, DIY LED DRLs
LeafSpy Pro + Konnwei KW902 ELM327 BT OBDII dongle
Loving my first BEV