Since you asked what was the 'best' way to clean leather, I would recommend leatherique.
It takes a bit longer, works best when it's warm although I've used it when the weather was cold (west coast standards) 45 deg, by
using a small SAFE space heater with auto shutoff.
I've used leather masters and while it's good. I prefer leatherique, it actually feels like it nourishes the leather.
I picked mine up from Detailed Image. I also followed
this very informative post on their site.