I prefer the clear chocolate myself. I find it easier on the coil/wick and visually it's easier to work with (I can see the graduations on my syringes better). Don't forget bittersweet chocolate. Setting aside the custard issue, I have found I cannot reach some chocolate flavorings without it. More like actual cacao flavoring (bitter, less sweet), it is useful in building a chocolate like you would use in the cooking world, i.e., adding butter, cream, sweetener, etc. to make a good dark chocolate. I will often mix double clear, bittersweet and milk chocolate in the same mix, to achieve a specific flavoring. Chocolates can be tough until you realize you will be mixing about six to eight flavorings to the mix to get the chocolate base just right, and having more flavorings allows for greater control and adjustment, expanding the flavor possibilities. For example, oreo cookies is difficult, without the bittersweet flavoring in the mix.
Of all the TFA chocolates, only the fudge brownie is good as a single, stand-alone flavoring, imho. However, by keeping the chocolates as specific flavoring bases and adding the other half dozen or so flavorings/ingredients, almost any chocolate is within reach with the TFA base chocolates. I very much prefer that greater flexibility as it creates greater potential and a wider flavor range.
At first, chocolates can seem daunting. But by adding the supporting flavorings, particularly watching the ratio of double chocolate to milk chocolate, you can get to almost any flavoring you are targeting. Really fun to play with, and perfect for 100DT experiments.