If you need that much flow, they are a good injector. The largest down side is the price.
Certainly nothing magic about them. As one goes to larger injectors, one may have to incur a higher idle speed because there is usually a limit on how low the pulse width may be in order to keep the injector functioning.
The upside originally was that the injector could be run at very high base fuel pressures without locking up-unlike the 50# injector and it needed no mods to injector drivers like some larger injectors. You can now get 80# injectors that need no driver mods.
There is no real benefit to the 60's as compared to other modern injectors if you don't need the flow.
