The old hydramaster system was the most even with the electric float and solenoid that injected as it filled. The problem was the float failing way before the rated duty cycles. Honestly, a 12v old school mercury rule switch used upside down beat the brakes off their floats. This was back when you could actually call Super Dennis and order parts from them directly, they don't do that anymore.
Without question dosing the tank is simpler and ultimately uses less chemicals on the rinse portion. The pump sees lubrication from start to finish and everything in the water system if on the soft water side to begin with has a better lifespan and reduced operating cost. Don't listen to us old bastards though, just say "ok boomer ".