Alloy pans are nice to hang on the wall and look at, but not nearly as nice to put on the car and worry about.
My MGA Twin Cam has an even nicer pan than the alloy TR - baffled, finned on the exterior has side conpartments for extra oil....and looks just dandy hanging on the wall of the garage.
Hit a rock once and you are out a valuable oil pan - and an engine if you don't notice the loss of pressure in time. Hit a steel pan on a rock and you just continue on, unless it gets pushed up against the crank in which case you'll hear the banging as the rods whack it and will know to stop.