The ring event that came with Chaos

Now that we have a chance at re-obtaining the rings, I just want to know if that 5% critical rate is better than the 1 extra attack on my Cruel Ring, and if so how much better is it?

Assuming normal attack (100% damage) and x1.35 Critical damage (mean),

Since Max Damage = 1.20*(4 * STR + DEX) * (WA / 100),

1.20*(4 * STR + DEX) * ((WA + 2) / 100) * 1.15 > 1.20*(4 * STR + DEX) * ((WA + 3) / 100) * 1.10
((Max Damage) + (4 * STR + DEX) * (2 / 100)) * 1.15 > ((Max Damage) + (4 * STR + DEX) * (3 / 100)) * 1.10
0.05*(Max Damage) + 2.30*(4 * STR + DEX) / 100 > 3.30*(4 * STR + DEX) /100
0.05*(Max Damage) > (4 * STR + DEX) /100
5 * (Max Damage) > (4 * STR + DEX)
5 * 1.20*(4 * STR + DEX) * (WA / 100) > (4 * STR + DEX)
5 * 1.20*(WA / 100) > 1
5 * 1.20 * WA > 100
6 * WA > 100
WA > 16.67

Therefore, Critical Ring will be better than Cruel Ring when you have at least 17 WA in total. Which is pretty much always.

Might have made a mistake somewhere. 17 seems a little too good to be true.