I tried the Bones mediums in my thunder hi 147s and had a problem with warping after one skate. The space where the bottom bushing comes into contact with the hanger is shallower than on low thunders, so it didn'y fit snug.
So I ended up swapping them over to my cruiser board, great response and snapped back into shape, which gives a nice snappy feeling on tricks, didn't realise the difference bushings can make.