Believe it or not, the Mastiff handles fine at that speed.....not light in the front end or any other bad issues....that is of course a straight line run on the open interstate....I damn sure wouldn't want to try to go around a curve at that speed....not even I am ballsy enough to do that.
You really have to have a 'built' motor to continually run it that hard day in and day out...mine had a lot of good parts in it, Jims pistons,clearenced and jeweled crank, .659 lift S&S cam, lots of head work, etc., and never had a seconds trouble with it, EVER.
What people don't understand is you can't just put in a big cam, pipes, and re-jet it and have a hot rod. It will run a hellova lot better than off the showroom floor, but won't last if you run it hard. For most, it's good enough....I, like many others on here raced cars, dirt bikes, etc., so I like to roll when I'm riding...I remember a sign hanging in a speed shop i used to go to that read, "Speed costs, how fast do you want to go ?" Pretty much sums it up.