I've gone through three boxes now. The best thing about it is that it is low sudsing.
Except for some tablets that had returned to a powdery state before being opened, the pucks would not fully dissolve except in hot water. Cleaning power unaided was marginal at best. Actually, "laughably bad" is a better description, but perhaps it is unfair to expect any 40 year old product to work as new. I've had good results with some other old detergents, though.
You do get the phosphates, however, and you can add all the enzyme/bleach boosters you like and get good results.