Stick with the carnolians, they are a gentle breed and you will be better off in the long run. Hybrids tend to get nasty unless you replace them on a regular basis and that can get costly. I think there is some promise in a mite resistant bee, however I don't think the process has matured to a point where it is worth while for a hobbyist. Just my 2 cents.
Unless you keep a very close eye on your hive, AND know the signs to look for, you would be playing russian roulette (no pun intended) with your hive. Mites can infest a hive rather quickly and sometimes it is too late to treat by the time you figure it out.