You do need to be careful of slugs with any small plants. I'm merely saying that hollyhocks are not as tempting to slugs as many other plants are, especially lupins.
Another reason I like Antwerp is that they are single. Most (all?) hollyhocks sold in garden centres are double, and not as attractive to wildlife.
T&M are also offering a new variety of singles this year called Halo. I think that T&M were offering also Halo as mini-plug plants earlier in the year. That's actually a good way to buy them. I was tempted, but didn't actually purchase.