These aren't TFA or CAP, but OneStopDIYShop has their own proprietary flavorings called One Stop Flavors and One Stop Blends...that are made to be stand-alone. Their Succulent Strawberry (a One Stop Blend) and their Blueberry (a One Stop Flavor) are both stronger, true-to-the-fruit taste flavorings. I've found also that each of them tend to get stronger in your mix a few days after you've made it. When used singly, both are very good, IMO. They have them in several different sizes, including sample sizes, and if you use the coupon code ECF or JFK at Checkout, you'll get at least an 11% discount on your total order.
They also carry the main name brand flavorings, too, like TFA, CAP, FW, etc. in case you need any of those.