IMO any good caranuba wax is best. Ranges from Meguire's bottom end of the range @ around £5 ($7) to Swizöl @ £4000 ($6000)
I've tried so many products over the years - just see what works best with your paintwork (yes this way costs a lot but IMO it worth it). Also i find using my fnger over light scratches works better as the wax get heated and melts into the grooves.
I have ended up with this for my black FD in original (PZ) black and find that its the best out of a huge range tried over the years:
http://www.zymol.com/zymolcarbonwax8oz.aspx