That's not the first time I've seen (run 4s-5s but not a 6s) What's the point of buying something that "can handle" a 6's, but it really cant?

If your blowing out diff's using what the manufacturer said it can handle "6's" one would think they would fix that problem. Instead they rely on people buying new replacement parts, making more money and customers setteling, going down in pack size. It's either that or you have to spend a small fortune just to get it to run on their specs.. That makes NO sense!