No experience with Johnson Creek but in my limited store bought liquid experience and broader DIY experience, the darker a liquid is, the faster it gunks up and the sweeter a liquid is, too. I can mix up a batch of strawberry and go 2 weeks without changing my EVOD coil. If I put just 2 drops of sucralose in 5 millilters, my vapor production will drop off by the 2nd refill and by the end of the 3rd refill, the coil is oozing sludge. 70PG/30VG. My iClear16 (long wick style) handled the sludge factor better than the EVODs but I don't like the warmer vape.