I purchased a $800 pair of dressage riding boots last fall and lightly broke them in and then put them away for the winter.  During winter, something funny happened...I got fat!  I gained 5, ok fine, 7lbs and on my small frame it made a huge difference (insert sad, pissed off face here).  Suddenly, when I went to try the boots on again since I have a horse show in 2 weeks, I could hardly zip them!  They hurt/pinched in about 3 places and when I forced them to zip up, it felt like a tourniquet on my leg.  I got a little panicked because of that non-refundable $500 entry fee I had paid and starting looking at boot stretching products.  I purchased this one for no better reason than I liked the no nonsense video and the price was right.  I was worried about spraying my high end boots but had little to lose at this point, plus the guy in the video seemed pretty confident.  I sprayed inside and outside of both boots in the problems areas, then immediately put them on and wore them for about 30 minutes.  I did spray a bit on the outside after 15 minutes.  Suddenly, the right one felt better and soon the left one did too.  I wore them a bit more for insurance and put them away.  The next morning, I approached them with trepidation, hoping the leather wasn't ruined or they didn't shrink back up again.  Thankfully the leather was fine but the fit was PERFECT!!!!!  Can you say custom boots??  Whoo hoo!  Easy to zip, easy to wear, perfect, perfect fit!  Thank you for a terrific product!!!  (NOTE:  for you dressage riders out there, I DID NOT spray this on the hardened outside shaft of the boot AT ALL as I wanted that to remain stiff as a board.  This product will soften leather and you sure don't want that.  Unless you do want that.  Then do whatever you want. :)