Treating leather boots?

[Canotrouge]

A lot of leather waterproofing have silicon in them and when I was working in an outdoor gear store, all the reps from the hiking boots company we carried, had the same thing to say, never use products with silicon in it cause it weakens the sticking threads! But I've use Dubbin quite a bit and nikwax and sno-seal, and some product from Norway that stink like crazy and the best results I've had was with Sno-seal. I need to try Dubbin again, to see what is the difference!