They were sturdy I agree but not so much fun to ride as I did for several years in Pittsburgh before the new modern cars were introduced. My memories included the roof top fans malfunctioning and popping on in February with the temperature 15 degrees outside and feeling like it inside.  In the summer the same fans would malfunction and the inside would get over 100 degrees. Not pleasant when standing room only. One woman fainted next to me and I had to use my coat as a pillow for her head. Then there were the numerous breakdowns when the catenaries would flip off or worse when all the passengers were let off in place to walk down the track to the next station. But they were sturdy!