The coffee flavors are my favorite flavor niche, and I have several favorites. Most are dark colored juices, so they do require more frequent carto changes. And many of them improve markedly if allowed to steep.
Best overall basic cup of coffee that I have found is Copper Creek's Coffee. Flavor is a dark roasted unsweetend black coffee. No old or burnt grounds taste like some coffees have. This can easily be an all day vape.
Copper Creek Coffee
I like cream and sugar in my real coffee, and the same is true with my vape. I add My Freedom Smoke's Sweet Cream to taste.
Sweet Cream E-Liquid - MyFreedomSmokes.com
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Vaperite makes some very aromatic and bold tasting coffee flavors that are usually in my daily rotation. Organic Double Espresso and Organic Kona Cream are both quite flavorful. They benefit from steeping, and for a little more money are available pre-steeped for immediate enjoyment.
Organic Flavored Double Espresso | Organic Flavored Juices | Vaperite E-Juices | Vaperite.com
Organic Flavored Kona Cream | Organic Flavored Juices | Vaperite E-Juices | Vaperite.com
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My all-time favorite flavor is Virgin Vapor's Organic Kona Velvet Milkshake. If you enjoy the frozen frappe's from a fine coffee shop, then this is the vape for you. This is how the creator describes her creation:
"This just might be my favorite flavor I've ever created! It's sweet, creamy and buttery with notes of caramel and rum all balanced out by a nice strong shot of Kona Espresso! It's so smooth and smells so good, I've had non-vaping friends try to grab it out of my hand to try it! Warning: highly addictive!"
Don't let the rum flavor ingredient scare you from trying this flavor, I have never tasted any alcohol flavor in this, and if it is, it blends in beautifully. A complex flavor whose background flavor notes are enhanced with higher voltage.
ECO Virgin Organic Kona Velvet Milkshake | Virgin Vapor | Electronic Cigarette Organic e-Liquid | Electronic Cigarettes
The Organic Turkish Dark Roast and Organic Kona Coffee Milkshake are also wonderful flavors.
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Espresso from Backwoods Brew and the coffee flavors from Dark City Vapor earn an honorable mention, too.