Just got this in the mail after waiting on backorder a few weeks.  No sanding or filing of the grips was required and installation was easy with just a small screwdriver and a larger one to take the grips off.

I just bought a SAO 226 Legion this week.  What does this slide stop do for you?  How do you grip your pistol?  Thumb on top of the safety?

Thumb on safety.  I was also sometimes bumping it with my support hand though by keeping it up high on the frame.  

I expect this will cure my no slide lock woes.

I might have to try one.  Either my thumb rubs on the slide or I hold the slide stop down.  I can't seem to find the right place for my thumb.

I'll go shoot some bullets this weekend and report back.  You have to be a little more 'deliberate' in activating it and if you have smaller hands your thumb might not be able to get enough leverage to press it.  That said it should be nearly impossible to fat finger it on accident.  

I actually flubbed a mag change on my first round in my first pistol match because it didn't lock and I didn't slam the full mag in hard enough to seat it on the closed slide so it fell out on the ground.  Pretty embarrassing.

Part number on that? I have a Sao legion on order and know it will be problem, I ride the slide stop on almost every pistol.

1201455-R is the part number.

Admittedly this smaller part did not totally fix my problem though it did help.  I can still bump it if with my strong thumb if I ride the safety but it is small enough that I do not bump it with a high support hand.  

I notice that my 20 rd mag doesn't have much spring tension on empty and it is the mag that exhibits the lack of slide lock the most frequently.  I took the slide off and tried different mags and the followers in the 15 rd mags definitely press against the slide catch lever with more force than the 20 or 18.  From what I have read the extended base mecgars use the same springs as the 15 rounds they are just allowed to stretch further.  I ordered some wolff +10% magazine springs to see if this can help me out.  

Next time I shoot I will also test some full power reloads instead of low recoil match style loads to see if this helps me and if maybe I should play with the recoil spring weight.

Is this directly from Sig?

Yes you have to call them to order one.  $26 + shipping

Very nice, thank you good sir.

Thanks for posting this.  I'm having the same issue with my P226 Legion SAO not locking back, so hopefully this will address the problem.

Just FYI. It's the same part # for the P224 as well.

It helps a lot but still required some practice to keep the thumb clear of it when riding the safety.  

It is out of the way enough now that my support hand does not bump it.

I actually have gotten a grip that now works for me and I'm getting the slide to lock back most, if not all of the time.  Need to continue to practice with it, but I'm cautiously optimistic.