I hope for you the roles are never reversed here. All this over $50?. Anyway I have spoken to John once years ago and we had a difference opinion and it was handled maturely. I have seldom hesitated to speak my mind on US car tools in general when I felt there was a misrepresentation of their products. A search will clearly prove that. However there are IMo a few possible reasons a deadlock is reached in cases like this, and one or two them cannot be changed by all the name calling in the world. Since John has a long respectable business reputation with many here, I suspect there must be some serious causes for this impasse, and they are following not necessarily in order, merit or probability:

1. The OP has been a total jerk and poisoned the relationship fatally
2. John has every intention of meeting his commitments and is close to doing so, and has no new info to share which if he did would likely only open him to more harassment
3. He has personal/medical/etc issues in the works
4. He doesn't have the funds to refund, and pride in admitting so is an obstacle
5. He's a full blown crook that has figured out how to buy an off shore island on $50 mopar scams
6. Or some combination of the above.