Sugar Cookie is very light, so 10-18%, despite being a wide range, is about where it needs to be. I'm not a huge fan of this one just due to it being so light. Others may love it, but my palate likes strong, intense flavors.
Captain Crunch & Berries mixes well at 10-12%, Rice Krispies at 10-14%, Creamy Caramel 10-12%, Peanut Butter at 10-12% and Dutch Apple Pie is best, for me, at 15%. IMO, DAP needs time to steep/age. It's pretty good freshly mixed, but after 7-14 days it's even better.
Raspberry & Strawberry are pretty good, as is Blueberry. I use them more as mixers as opposed to single flavors as I like more complex and layered flavors. For single flavors, start with about 8% and work your way up. TPA's Bavarian Cream is a good addition in lower %'s. Don't mix it too high or it may overpower the blend.
I know they service quite a few dealers, though I don't know which ones and they most likely won't say as that'd be a conflict between the two businesses. I've never tried KickBass' flavors, so beyond looking at names and taking a guess, I couldn't tell ya

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