I agree with @stug I've found Lowa and Nikwax products promote cracking especially at the toe flex area. I have been using dubbin for a couple + years on Lowa Rangers and Tibets with no issues. What I do, do is - warm my (dry) boots up in front of a fan heater (don't cook them!) as this helps the dubbin soaking in. Prior to every 3rd application I use saddle soap to clean the leather down as was recommended buy a old saddler as it stops the leather becoming too soft and ripping/tearing.
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