Hi, CAAB. There are a few things to get into here. Bare with me if it drags on… And, forgive me if you know all of this already! Better safe…
My first hope is that if you’re buying directly from Nature’s Flavors, you’ve done some research and know which of their many product types are safe to vape.
Nobody new to them should ever be guided to their front door without a good set of do’s and don’ts. ( @Dan_the_Man, I’m looking at you 
)
Acceptable product lines from NF direct are:
Organic Extracts
Organic Extracts without Diacetyl
Organic Coffee & Tea Flavors
That’s it. Dont try anything else.
To make it easy, and less expensive, head over to diyvaporsupply.com. They have many, many NF there and all of them are safe for our purposes. They’re all from the Organic Extracts line.
NF Extracts are alcohol based real extracts with no PG or VG. The Coffee & Tea line is just the Extract line with a bit of added VG to help coat the coffee beans… Which is 1 part of why it’s presumed that Kai’s uses them along with MF. Part 2 of the presumption is the flavors Kai’s comes up with.
If you study all of the flavors offered by MF and NF, then go read the descriptions of all of Kai’s VV, it is obvious.
Here’s where it gets weird(er)… Last year(?), MF revealed that they have been using PG all along. Sorry, Kai…) But, it’s a special bio-based PG derived from vegetable oil, and my wife doesn’t have any reaction to it like she does with standard PG-based flavors. They have since discontinued the old line and released 3 new lines of flavors. Premium line, most like their old-school formula, uses the vege PG. Silver line is Alcohol based, zero PG and even more concentrated than the original, Gold line is or is going to be Coconut Oil mct based. Never buy the Gold line for standard vaping.
Ok! With that out of the way…
As @fidalgo_vapes wrote, MF are some fantastic flavors. Dont let the price scare you off. Their Dark Chocolate is a must have. At 0.3 to 0.6% needed, it will last. Their Strawberry, as also mentioned, might need 2%. A rarity for MF, but still a fantastic flavor. 2% is actually pretty low compared to some more standard flavors, and you won’t have it fading away…
NF Strawberry is also fantastic. Also less expensive. It goes well 1-3%.
If you’re into the Virgin Vapors for the PG-Free aspect, pick up some Rick’s Sugardaddy Sweetener at diyvaporsupply while you’re there. No PG there, and good at 0.5% if you let it steep.
I haven’t had VV since I started diy in 2017, but they were very tasty. But, we were paying like $17+ for 15ml of liquid! That is what led me to make my own. Very little PG-free liquid available and what was available was crazy expensive.
Not knowing what A Kiss Goodnight tastes like, I can’t tell you which flavors they may have used. But if I were to try it blindly, I’d start like this:
Strawberry MF 1.5%
Strawberry NF 1%
Dark Chocolate MF 0.6%
Sugardaddy Sweetener 0.4%
If you only want 1 Strawberry in there, I’d use NF at 2.5% or the MF at 2%. Combining them, I try not to use them at full potential mix %.
Now, if you are mixing with only flavorings and VG…I add PG to mine… you may need to push the flavors up, but I’d try the above 1st. If it lacks in flavor after 4 weeks you’ll need to nudge the flavors up. Or, down… hard to say unless you try. Sometimes, less flavor % can boost flavor because you’re muting out, sometimes you dont have enough. All part of the fun. I actually hope you like a little PG in your mixes. It makes things much easier. I had no luck trying to help a mixer out recently mixing only VG. We just couldn’t find the right combo. It will take you putting in some trials and time to get it right for you if it doesn’t satisfy right off the batt.
Good luck! Ask me anything and I’ll do my best to answer.
Edit: (I knew I’d miss something). When I mentioned MF %'s up there, i was referring to the original formula! I haven’t tried the new Premium line. Hopefully someone can chime in and say if the Premium Dark Chocolate and Strawberry are similar enough to the old formula for the % to stay the same, and if the flavors are equally awesome.
just hate to think someone would go in there and click on “Concentrates” because we use that word for everything. They’d be in for a bad time mixing with NF concentrates. Gums and stuff only suitable for drinks and food
