General

I am not sure why you are asking the question of PDR over Status Resistance. If I am not mistaken, with the Cygnus stacking link skills, hyper skills, and etc a Merc can obtain around 70% Status Resist w/o sacrificing boss% or PDR. This is ignoring the additional options, Bit System, and Monster Life, and any other future Nexon update. I am going on the record of saying that outside of a new broken class, Mercs are going to be the first to achieve close to 100% Stat Resist (I don't think a class has this yet).

TBH, I do not know of a situation where you can sacrifice PDR for Stat Resist or vice versa in the first place.

@QuantumLegend, @askmiller: You'll need to take back your words when Unlimited comes , when 100%PD ignore is no longer achievable (you'll appreciate having that skill).

But for now (to answer the OPs question):
With Spikes Royale(+Hyper) and say a Hob King monster card set you'll have 55% PD ignore, leaving 45% defense which at a 40% rate we can ignore 100%. i.e. In terms of average damage output you're lacking 27% of your damage. Which is a fair bit but with little care this is a great number compared to other classes.

Ergo: %Bossing is, was and will remain to be our desired potential lines on our weapon(s).

I wish defense break just gave us %ignore defense instead of %chance to ignore all defense It really makes getting %ignore a lot less useful for us. Your choice I guess, but just value %ignore at like half of what you would on another character.