I tune to E standard with 10-52 strings and those stupid stock Edge Zero springs aren't tight enough. (Note: on a regular Edge or OFR I never had that problem with 3 springs in parallel with the claw at least 5mm from the cavity wall).
I even had two luthiers look at it and try everything and even screwed all the way in (max spring tension) the trem was not balanced.
It's a 6-string Prestige and I had to buy 7-string Edge Zero springs (2SUX5BA007) from Rich.
Stupid. I understand why this EZ gets so much hate, I like the feel and the fine tuners are fine, low-profile and all whatever, as long as it stays in tune but come on, they should have made the stock springs tighter, OR given more room for adjustment or whatever.
Well, it's a good thing for you if that's your only beef with the trem, as that's the easiest part to replace!