Is saphir really that much better than Kiwi?
Yes it is. Many years ago I only used Kiwi, and always had problems with polish build up. After time, I also had shoes that cracked and split -implying that the leather wasn't getting adequately nourished. So I switched over to kiwi parade gloss. After that the polish build up was still a problem, but the parade gloss did appear to nourish the leather better.
A few years back I finally tried a pot of Saphir creme and while it's much more pricey, I don't plan on ever going back to kiwi. The creme is a really good start to saphir as it is really rich in pigment, so adds a lot of colour (so either match the shoe colour well, or if you want to change the shoe/boot colour tone, go with a darker creme as required) and it seems to really nourish the leather well, to stop it drying out and keep it like new.
Now that I've been using their stuff for a while, I use renovateur to really feed the leather, only from time to time. I use the creme as my regular shoe-care routine, because the pigment will hide any scuffs etc. and it feeds the leather well too. Finally I've got some tins of the wax polish, just to shine and protect the toe and heel areas, where the kids typically stand on my feet...
I'm not saying this is how it should be done, but my shoes always get comments on how well kept they are, and this routine works for me. Saphir is more pricey, but all of my shoes just plain-old look better since I've switched to it, so it seems worth it.
Maybe just give it a go with a pot of their creme?