I've bought their prebuilt wire (spools of 2x26/26, 2x28/38) and I always find the resistance of the coils I wrap with it is off each time. Coils are wrapped really tight, so don't think that the factor, but it does make me wonder if the wire isn't always as "pure" as it could be. No problem with cleanliness, but it has made me want to shop around for wire to start building coils myself (rather than just wrapping them). Grabbed some wire for practicing from there, but I'm more tempted to buy from Juice Junkie next time as I've bought some pre-made coils that used their wire and they were spot on where they should be resistance wise and have had great longevity. Only problem is that popular wire gauges are often out of stock. Still yet to check out Stealth Vape.