I would imagine the ones in Thailand all went to the famous doctor in Thailand... But I don't think that's the key here, transitioning before or in your twenties is best, after about that time you have some permanent changes from your respective sex hormone, but in the same breath feminine men and masculine women do exist, and they can be handsome/beautiful in their own way. Even after your twenties starting on cross sex hormones will produce major changes, and there's no way to predict what you're going to look like exactly other than just doing it. I do recommend avoiding stopping if you do start though unless it's just clear it's not for you and you'll never start again. I don't have any studies, but I have to imagine you'll get better results from a straight run than see sawing your hormones...
