The main problem with the older bearings was binding. With the newer bearings, axial play seems to be the problem. Grab hold of the stationary star, and see if you can move the bearing housing along the stationary star. Heat, as you mentioned, is another give away. They can also sling grease before they give up the ghost. The bearings are sealed, but are installed with grease across the upper and lower surfaces. This grease can melt and get flung out if the bearing gets hot. On the outboard end of the bearing housing, there should be a line of sealant. Make sure this is in good order, otherwise there is a risk of water getting inside the housing. Can't really think of much else. Bearings were always a throw away item during overhaul, but we did check them for play before biffing. Found a couple that had a wee bit of roughness, but only remember one that was kaput, but we couldn't verify it's total time or TSO.
Sounds like you were unlucky to get a bad bearing, and lucky to hear it