Response from John over at RE . . .
There are a lot of variables with any install, but ensuring a part is properly tightened is definitely important. With two reports of clunking for a few weeks and one report of a bolt being gone, well, folks, I'd definitely make sure to tighten everything down and double check after a few miles for good measure. That's good mechanical logic. What we did to simplify the install is ditch the dual washer aspect, and went with a wider head bolt. Less moving parts, less chance of incorrect install order, etc. The kit comes assembled as it sits on the vehicle and we have posted instructions online as well.
ANYONE with the older hardware setup, with the washers, can get a replacement bolt no charge, and you'll only need to undo that bolt and remove the washers. You don't NEED to do this, but we're here to help if you're concerned. Plus it makes you check the bolts. That's good. For everyone who's got it in and loves it, thanks! For anyone on the 'flimsy' train, you do you. Sometimes a fresh design approach can change your mind.
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I will say that he was very helpful and open about the situation and we went back and forth on discussion about this. In the end, I've decided to go ahead and put an order in myself (that's how much I believe this to be a one off situation). Will report back when I install.