Guys - this debate has now taken a turn away from Mahogany / red / neutral. I wrote to G&G to get their recommendation on which Saphir cream to use for vintage cherry.
First of all credit to them to respond to my query so promptly (within a day). I have always considered their shoes to be the benchmark in RTW and their customer service makes me feel good about my choice.
Response was as follows "We recommand using Saphir medaille d'or cream in medium brown or burgundy. A rotation of these two creams allows the color to gain a nice depth with time.".
Only problem is that I ordered the Mahogany and Hermes Red creams already
in the end i'm sure you can get away with Hermes Red, Mahogany, medium brown, and neutral. You can just alternate shades overtime as you want to modify the color. If you want to keep the shade as close as you can to the original, you can just adjust overtime. I like to keep the general color but to let it shift slightly overtime so it builds more depth so I try to alternate between a slightly lighter shade and then a darker shade with the occasional neutral or very dark color added in once in a while.