u should be good on any kite that flags out on a single center line here's the list which I made for another thread:
single center line flag out: ozone, slingshot, liquid force, wainman, blade, naish
Do not use any of these bars
Y-mini-5th line quick release: cabrinha, best, north, airush, epic, switch, gk, core
If you use the Y-mini the kite won't fly right, the Y pinches the kite and you have no promise of complete depower as the Y depends on the bridle operating a certain way.
The above lists are only for 2012 and later, i would have had to make a spreadsheet to list all the different years and such.
I know what you are saying, the only thing I don't like about slingshot is how small the grip on the quick release is. Liquid force has a much wider grip very nice, but they have the stupid detachable chicken loop which means two seconds of forgetting to clip on the chicken loop and you can lose it. Not real familar with the 2012 Naish control bar, but if you like it, should work. The ozone megatron release is solid and simple but it's not a center push it's a side pull, old school. Can't wait for the ozone 2013 control bar.
I would not use the ironheart with any slingshot bar, it pinches the kite something terrible feels like the kite has no power.
Not real sure how knotwindy modded his ironheart, but you have to take out that Y or the rally wont fly rite.