Don't forget that there is a scale effect, the more wing area "over all" the higher that number can go I think.

Like on a 28% I would go no higher than 30 oz/in. ( depending on your location, altitude, air temp) for good 3d.

On a 35% you can go to about 32 oz/in and have the same result as the 28% on 30 oz/in.

On a 40% you can go to about 34 oz/in and it will fly like a 28% at 30 oz/in.

Or so it seems to me.

Also altitude were you fly, and temperature, will have an effect on lift.

Cooler air = more lift

Denser air = more lift