I 'think' I know the answer to my question, but I wanted to make absolutely sure. I'm not ready to go the complete DIY route, but would like to test several flavors to get the strength to my liking. I'm a big menthol fan, so I'm thinking I can put 5mL of pre-mixed menthol in a bottle and add a few drops of flavoring. I've been researching this on the forum and haven't run across anyone else doing this way, so that's why I want to be certain that it would be okay to flavor my menthol this way without having to do anything else to it. Does anyone see a problem with this?