Some tough semps.
S. 'Oddity'
S. 'Sunset'
S. 'Cafe'
S. 'Bronco'
S. 'Blue Boy'
S. 'Grey Lady'
S. 'Limelight'
Any of the S. globiferum (rollers) as twit mentioned in his above post. They are tough and amazing plants to have in the garden or containers.
Most of the S. heuffelii should work for you.
I grow the above semps in full sun, and they have done very well in out hot/drought months of July, August & September.
Others may have more suggestions from their experience with different ones.
