Super strenght/shield lvl 50. Where to put 6 kinetic crash melee damage sets?

I got the 6 sets of crushing impact to put somewhere.
I think is better to put them in knockout blow than foot stomp?
My brute is SS/SD lvl 50 and shield charge already slotted with 6 Obliteration.

...what?

Do you mean you have all 6 pieces of one set of Kinetic Crash (it's NOT a damage set, it's a Knockback set), and you want to know which of those two powers to slot them in?

Uh...neither.

Unless, of course, you're using your SS/SD for farming ONLY; then I guess you could put them in Knockout Blow. But using your heaviest hitting ST attack as a set mule for, what, an extra 7.5% Recharge Time? Okay.

Damn, lol
I meant crushing impact...
Sorry for sound crazy, but I been messing with IOs sets today and I switched names, lol
I got all 6 pieces of crushing impact.

Depends. Most decent sets, when you have them 5 or 6 slotted, will hit E.D. on recharge and/or damage. ED=Capped, (not really, but effectively, yes). Is this a mids build you're doing, or are you just making a toon the old fashioned way, by trial and error? If you're just slotting a 50 as best you can without a stat cruncher, then I'd say it shouldn't really matter what you put crushing impact in. It's a good set for most any melee power unless you're attempting to build a character with level 40 crushing impacts slotted in low level powers so that you can exemplar for running numinas and such. Personally I don't do that, most 50 builds are good for exemping to task forces like numina.
If you are trying to make a build like that, then go ahead and put crushing impact in your low level powers, and save your high level, heavy hitting powers for holding purple sets or touch of death and mako's bite.
A heads up too. Shield is one toon that you want to chase melee/range/aoe defense as opposed to s/l, nrg/neg, and fire/cold. Mako's bite and touch of death are good for raising your melee/range/aoe defenses. If those are high, then crushing impact in the rest to get some recharge is fine.

I'd suggest using only 5 Crushing Impacts and sell the 6th on the market (or save for a later character). For example, if it's a character with a lot of global accuracy, I'll leave out Acc/Dam and go with the other 5. Now if it's a character that has endurance issues but plenty of global recharge, I'd dump Dam/Rec instead. You'll get pretty good modifiers across the board (especially damage) with just 5 as it is. Lastly, the final set bonus for CI (2.5% psi resist) really isn't worth the 6th slot which can be put into a different power if your build is tight (as most brute builds are).

Thank folks...
But then, even if I slot only 5 IOs (with 5 I got enough damage, accu, rech, and end reduc.), it is better in knockout blow or foot stomp?

On an SS/ brute i would say leave out the Acc/dam because acc is actually kind of useless against most things because your Tohit should already be close to the cap even before any acc and you will only gain about 6 dmg in KoB if you already got the other 5 in it which is at most 0.7 or so dps.