Coffee flavors I've enjoyed the most in the past year (in no particular order):
Kona Coffee & Kona Velvet Milkshake - Virgin Vapor (haven't had any in a long time, used to be an ADV)
Espresso - Backwoods Brew (best after steeping for at least a month)
Malted Coffee - Darth Vapers (similar to KCM)
Tiramisu - Ahlusion
I've tried quite a few cappuccinos and mochas from different vendors, but they were either too sweet or not enough coffee flavor for my taste.
Now I mostly DIY my coffee vapes.
If you don't want to buy DIY coffee flavors and you're looking for a really cheap coffee vape... try extracting your own favorite coffee in PG and then add some VG and Nic. It's fun to play around with using different flavored coffees. Then if it doesn't float your boat as a juice, you can just brew it up into some real coffee.
You can find a whole thread on extracting coffee in the DIY forum. If I can do it, believe me, anybody can.