I did a TCI Rattler myself. IMO a good aftermarket harmonic balancer is a worthy upgrade from a durability standpoint. They dont spin on the hub like a stocker under stressful situations.
the Fluidamper has only four parts, the shell, hub, inertia ring and fluid coupling. and two of those parts are welded together. Leaveing only the moving parts to wiggle around like there supposed to.
The only thing I've ever heard bad about Fluidampers is that at high RPM for extended periods of time the fluid can puddle in the balancer and act like a big weight on the crank snout, but I've never heard anything more substantial than heresay. To me that would have to be substantually high rpm, given the small amount of space available for it to puddle and force the inertia ring to the other side. I think most of the guys who talk about this stuff still believe in stamped steel rockers, big dome pistons, and something called a 3/4 race cam
, Oh and ported cast iron exhaust manifolds