I only use this Huberd's and Obenauf's.

Grease or Oil, on all my work boots and cowboy boots.

The stuff is great for waterproofing, keeping 'em clean so you can beat 'em up, and for breaking in and treating the leather.

It's got a bit of a pine tar smell, and it will darken the leather.

I've got a number of pair of quality boots, Danner and Bates, and they see a lot of use and abuse, and this stuff gets 'em broken in quick, nice and supple, sometimes they darken up for just a spell, sometimes they get and stay darker, depends on what color you're starting with. Some of the Sand/Coyote boots got and stayed darker, some returned to out-of-the-box color.  The darker boots, brown/wicker and black, well, they were dark to begin with.

I'm tellin' ya, my boots look great and are in great shape. Even when they get beat up.

Give it a try, I've got it on boots from $100 to $500 ... and I'm well pleased.