Discussions are fun man lol! That’s kind of what we do here to make things better for the community!
I will say you have valid points here. As a brewer I would think you would want to know what you are working with first.
@MisterSuperGod is on point with his logic I believe.
I think testing the raws could cost you less in the end. Like MSG said what if the finished product comes back under dosed? Are you going to change your price and labels to match what the product dosage test reports come back as? Or just not post the bad results and take it as a loss?
If you are confident in your brewing skills, even though a mistake can happen, I think raws testing would make more sense. Raws testing can’t be done by the customers so that’s entirely on you and will also keep your supplier accountable! This will also take out the variable that the raws are the problem making it easier to narrow it down if a problem arises.
I understand just testing the finished product to save some cash and to see what it’s dosed at ‘killin two birds with one stone’.
But...
If you offer a good incentive for customer testing then it will cost you even less wouldn’t it?
We know roughly how much a vial costs to brew. Pennies. Wouldn’t that be cheaper to just encourage customers to do the finished product testing randomly?
The main thing here is that you’re testing! You have to figure in cost, and find a system that makes sense and benefits you and your customers. Plus encourage customer testing with that process.
We know it will take a little time to get ahead on testing to the point you’re out in front of it. As long as you’re testing now it will get you to that place even faster imo.