It has served me well over the years, and you are right it is basically a solid rock and does weigh a lot.
I love the old SME tonearm, it will balance a cartridge weighing zero grams,,,plus it has the fluid damper and the pulley with the 1 gram anti-skating weight. I installed it myself and have to say it exceeded my expectations. I even found a vial of the fluid to refill the reservoir on e-bay last year,,,so it is as good as new.