My daytime employer subscribes to Wufoo's mid-level plan and the experience has been fantastic. I was worried when they sold the experience might change, but so far it's been nothing but the rock-solid steady performance and smart feature enhancements we've had since day one.
I can't remember when, but not too long ago Wufoo sent us a hand-written thank you note for being their customer. It blew me away.
I second patio11's comment below: "I wish there were a lot more Wufoos."