I ordered about 10 10ml bottles of TFA flavors from Wizard Labs to do a trial run and so far, I'm not impressed at all. I know taste is always subjective and with that in mind, stick to flavors I know first and experiment later.
I grabbed Key Lime, Graham Cracker*, White Chocolate, Bavarian Creme, Cotton Candy and a few other sweet flavors mainly because I have the most experience cooking with the majority of those, and eating the other (i.e. cotton candy). Unfortunately, the majority of those flavors were weak at the suggested levels which average 15% or less.
I worked up about 8 10ml bottles and 3-4 5ml bottles testing each flavor individually and a few combinations (such as key lime and graham cracker to make key lime pie) varying at 12-15mg nicotine and a 60/40 mix of PG/VG, the results:
Caramel
No major complaints on this one. It's pretty close. I feel it still needs some work as it can be a little deep at times.
Key Lime
Seems great if you can vape the bottle fast when it's fresh, but steeping for 3 days now, it's almost become rancid.
Sweet Tart
I LOVE sweet tarts and this is not even remotely close. It's flat tasting, doesn't have that burst of flavor and I'd never order it again.
Graham Cracker
The flavor seems muted when steeping. It's recommended that this flavor be mixed, but mixing with key lime didn't do it any justice and none of the flavors I bought would really mix well with this. Perhaps Bavarian Creme, but I've not tried it.
Bavarian Creme
This one, out of all 10 ordered, is probably the strongest. At 15-20%, it's almost overpowering, whereas at 15-20%, the others don't quite meet my own personal standards for bringing out flavor.
White Chocolate
Tastes nothing like white chocolate, not even close. I could drink a cold white hot chocolate, vape this and never know the two were remotely supposed to taste anywhere near the same. It's not creamy and honestly, I can't describe the flavor.
Creme de Menthe
It's nice and minty, cool on the throat and could be overpowering if used in high concentration. I can't really say anything bad about it, but it's definitely not what I expected Creme de Menthe to taste like (nor does it taste like anything I've had before).
Brown Sugar
Deep flavor, can be very overpowering and not really something you want to vape by itself.
Waffle
It's a toss-up on this one. It's not horrible, but it's not great. Compared to a premium vendor such as ECBlend, this one doesn't come close.
Marshmallow
I'm still debating on this one. It doesn't really have much of a marshmallow taste. It's somewhat light, but I still feel it too needs some work to really hone in the flavor. It's almost to light to blend on it's own, but doesn't mix well with Key Lime at all (tried this based on a recommended recipe for an alternate Key Lime Pie - combined, they almost taste sour, as in rancid).
With that being said, I try to avoid flavors with alcohol in them as I don't want diluted flavoring. Perhaps this one is on Wizard Labs end, but none of the bottles I received stated that alcohol was in them, nor did they on the site, but it's VERY clear that many of them do (some do not). I've not yet contacted Wizard Labs on this one, but I may as it's a bit misleading.
Edit: Misleading due to the fact that their (Wizard Labs) labels state the ingredients, none of which list alcohol, but one whiff of the flavors and it's very clear there's a good amount in there.