I ordered 5 plants from them. 4 looked great. One had wilty leaves. I emailed some pics and got an immediate reply. I followed the suggestion of removing the sickly leaves but the plant did not perk up in the following weeks. I sent further pics and was offered a refund or replacement. I requested and was granted a credit on my next order. My other four plants are doing well and went in the ground yesterday after 3 weeks in pots. I was very happy with the prompt replies, advice and friendly customer service.
The fancier mums are generally considered hardy only to zone 8 but I spoke to someone at my local Extension who said he'd had very good luck overwintering his in the ground if they were in a sheltered position closer to his house. The mums are reasonably priced (I think they were 5 bucks a pop) so I don't mind growing them as annuals if it comes to that.