call TT-QQ,AQ,AKdepending, and 4 KK+,AKdepending + a few bluffs imo.
Yes its nice to have suited cause they can flat more easy when they have position on you.

man you calling  3bet oop with TT ,JJ ?how you play post flop??? 

I'm pretty sure you can choose better hands than Ax; Kx hands to 4bet bluff.

Smaller PP have more equity vs villains 3 bet range, and whilst I think you're right most of the time you won't see a flop, its nice to have decent equity when you do.

Assuming villain 3bet/ calls with KK-JJ,AQs+,AKo then we have 37% equity when we see a flop vs 28.3% equity with A7 (if we use A7s its 31.2%). Adding back in all combinations of AA drops our equity by ~2% across all the examples.

I think the added benefit here is that we know when we hit with the PP.

Just to be sure, I'm absolutely not saying we should 4 bet all PP by any means just that they seem better to me than Ax (and AXs is defnitely better than AXo)

AX and kX is good because block strong hand ,and it is better than PP,and see flop after 4bet is in minority of time ->than rather have blockers than little better equity in some time when see flop

Krankie, would we would prefer 4 bet bluffing AXo than suited, as they are less playable? 4B bluffing a hand like AJo has good card removal effects also, and AJs is going to flop more equity with BDFD more often, so may be a better candidate to call?

This is a good read also:
http://en.donkr.com/Forum/optimal-3-bet-4-bet-5-bet-strategies-in-nlhe-6-max---part-1-533561

If we are 4 bet bluffing with Axo and Kxo the frequencies that villain has their strongest 3bet/5bet shove combos (AK, AA, KK) will also drop. Where as if we are choosing PP, they will have these more often?

Hmm, yep agreed to all above. I was looking at it from a slightly different angle of equity when villain calls our 4 bet. But I agree that card removal here makes villain less likely to have a premium hand and therefore less likely to 5bet.

More work required for me here I think...nice article by the way

Getready2rokk:i totally dont like your last post here.

We could conceivably design a defense strategy where we fold weak hands, 4-bet strong hands, and call with medium hands, but this is not a good strategy out of position with 100bb stacks.

You have poor implied odds (due to low stack/pot ratio and being out of position) when you call for postflop value with implied odds hands. And it's difficult to steal and outplay Villain when you are out of position. And what you absolutely cannot do, is to call and then play fit-or-fold postflop. It will be much more fold than fit, and you are simply burning money by letting Villain c-bet his way to riches and early retirement on your expense. 

The other 2 parts are here:

http://en.donkr.com/Articles/optimal-3-bet-4-bet-5-bet-strategies-in-nl-holdem-6-max---part-2-340

and

http://en.donkr.com/Articles/optimal-3-bet-4-bet-5-bet-strategies-in-nl-holdem-6-max---part-3-351

what methods you use for 4bet bluffing OOP ->combo methods (something like AQ,AJ(AJ in 50% of time) -blockers)=12%

or generator of random number and just 4bet in 15% of time your 82% non value range (12% total range)??

This is the part that confuses me:

If we are opening TT, 99, JJ, AJs, AQs in EP - and we are 3bet by say CO or BTN, how happy are we 4 betting?

They seem a bit strong to 4bet/fold with these hands, and yet it doesn't seem like a good idea to split our continuing range into {Call, 4bet} as this makes our range much more defined and easy to read?