Insanely horrible. For starters, I must get the same ditz answering the phone every time I place an order for delivery. My order has NEVER been correct. My calzones have always been made wrong (either adding or leaving out an ingredient or two), I have had items added to my ticket without me ordering it and I have had items left off my ticket. The delivery drivers are always late and they always seem to slide my pizza around so that it's always messed up. And now let's talk about their pizza...the thin crust is always so insanely soggy that it actually sticks to the pizza box. Not to mention their sausage is nasty. They also don't cut it all the way and the sauce is horrible.
As someone who lived in Chicago and was personal family friends with the founder of Rosati's, I know that the Family would be embarrassed to see this quality, or lack thereof, be handed to a customer.