MissusD,
Correct me if I am wrong but are you saying that you have just completed, i.e. just got your keys and have taken over full ownership, and you have already experienced appauling customer service, faults and the like?
Don't want to burst your bubble and I sincerely hope that I am wrong but now that they have your money and you have taken the property off their hands, I suspect you are going to see a different side to Persimmon.
Most developers do pull out the stops until they have your money. Once this happens getting anything done is a nightmare - which is what most complain about on this site.
Perhaps your praise is a little premature. Would love to be proved wrong but after 5 years of dealing with another developer (Bett Homes / Gladedale) I haven't, yet.
Colin.
www.abadbett.com