I'm not crazy about minis either, but I do like the ones from Palatine because they're grafted onto R. multiflora and grow a bit larger than the own-root variety. Marriotta is said to be hardy to zone 6, but that's when it's planted in the ground. I think container roses are never as hardy as the ones in the ground.
My personal favorite of these "dahlia" roses is Vintage Visalia because it's a floribunda and it grows larger than the others. Mine's over 3 feet tall, even though it's an own-root rose, and I have no complaints about its resistance. It does better than many other roses in my garden in that respect. It also received an "excellent" rating for disease resistance on HMF.com.
