Instant fold against a decent opponent.

How does his image get a boost by a shove? I expect the vast majority of people to shove here with KK.

Of course this is a situation where a read would be incredibly helpful. If he's tight/solid you can get away, if not you should get it in. Frankly I think you can probably stick it in every chance you get with KK preflop and not lose money on it so I lean heavily towards pushing here. I don't feel bad going broke with KK vs AA, to me it is simmilar to set over set, in the long run you'll get as many as you give so it's a break even proposition if nobody ever folds KK (which is pretty much true) and every time YOU fold QQ/AK and THEY don't you make money.