I have hundreds of 10ml bottles and live by them. Until something is proven, I always mix them small. For sales, you buy whatever you are selling. I was glad to see BCF was selling larger quantities.
Small 10ml bottles are also a lot easier to rack up, and don’t obstruct the bottles behind them. You can’t always use small bottles though, especially for your daily use flavors, which may cause constant 10ml re-filling.
I use 5ml bottles to make a tester of all my flavors and 10ml to try out recipes. I get them super cheap on amazon . Its like 100 for 8 bucks. For finished juice its 30ml and 60ml usually.
I always only make 10ml when I try new recipes and only then will I make larger amounts if I really like something, that way I waste far less if I really don’t like it. As for scales, I was reluctant in the beginning going from syringes to scales but it was the best move I ever made when it comes to DIY, it’s so much cleaner and saves a lot of messing about with cleaning separate syringes etc. I bought one that can run on mains electricity and more importantly doesn’t time out on me in the middle of mixing a recipe. Good luck.
Mixing by scale is a nessesity . My setup for mixing consists of 3 pour bottles and a scale. Why would anyone want open every bottle , use multiple syringes you gotta clean and hope you dont get cross contamination and have to open up every flavor bottle. Just makes no sense.