I have never had to really break one in, those that do say it can take way more than 100 miles. I have several of many models, ages, miles and presumably levels of break in. The one or two that were not reasonably comfortable soon enough, I loosened the tension screw a couple of turns, treated both sides of the leather moderately and rode until they started to cooperate more with my backshide, tightened the screw back up and went on my merry way.

Some will say not to use this much treatment or ride it with the screw loose, well if you can't ride it, what does it matter, it will sit and become more rock hard until it cracks and becomes useless. It can always just be used for show but I will make it usable so it can do the job it was made for. I have several that are a few years old now that are doing just fine, if one or two of them blew up or sagged out tomorrow, so be it, leather is a wear item and yes these can be expensive but the absolute cool factor, cred and cachet combined with the comfort achievable is well worth the cost and effort if necessary, fortunately for me the effort is and has been minimal which is lucky, I am a huge fan and would still be even if they didn't work well for me.