How good is the EdgeZero compared to other tremolo systems?

I have been thinking of getting a RG8420ZD for a while now and want to make sure that the EdgeZero is a very good tremolo before I make the purchase as you can still find EdgePro models around.

Is the EdgeZero your personal favorite Ibanez Tremolo system? Or is it simply a very good one but not the best?

I understand the studs need replacing, but after that, is it a very good tremolo system compared to an OFR or EdgePro/any other really good tremolo?

Thanks for any help you can offer. Beyond the EdgeZero, do you think it's a wise decision to go with the RG8420ZD J Custom? Or should I be looking at older models for better quality?