Crit Focus Lines

[Seryph]

So I'm looking at a Blade Bound Kensai build and have been looking at a number of different options, but the one that has me kinda on edge is the Crit Focus line.

Using Kensai to qualify for the various crit focus lines has me doing something like this

9) Critical Focus
11) Improved Critical, <misc feat>
13) Staggering Critical
15) Blinding Critical
17) Critical Mastery, Stunning Critical
19) Open

Now, the thing that makes me question is this, the save is fort save, made up by 10 + BAB.. At 13th level, a Magus's BAB is +10, which means the Staggering Critical has a fort save DC20. Even against a mage with an average con, having a modifier to fort over +10 is not an unreasonable assumption, which means at least 50% of the time, the Mage (probably the weakest save out of all of em) will save against the feat. Even at 20th level, it's a DC25 fort save, which pretty much anything will be able to make in their sleep.

So I guess the biggest question I have, is it really worth it to burn 4 feats on effects that will be saved against the majority of the time? I mean in practical application, does this play out differently than the numbers are coming up with? I realize all the Crit line of feats have backup effects as well if the person saves, but even with that, do you guys find that it's worth it, or are there better uses of the feats?

[DreamAtelier]

Take Bleeding Critical instead.

[Mauril]

Staggering Crit always has an effect on a crit. The save reduced the staggered duration from 1d4+1 rounds to 1 round. But that's still one round. Same for Stunning Crit. A failed save and stunned, a passed save and staggered. These are essentially Save and Suck spells.

I would agree that Bleeding Critical is better than Blinding Critical though. 2d6 bleed per round, no save, is pretty good. Using Stunning and Bleeding on each crit (at level 17) is a sure way to kill things fast.