Unbelievably useless. After screwing up closing my account and continuing to charge me for months, I spent an hour in total (no joke) on hold. Eventually I manage to talk to someone who can do something about it, they promise it will be refunded.
The refund comes through a week or more later, and they screwed that up too. Sent me less than half my money back.
So here I am again 'we're sorry for making you wait blah blah blah' another morning wasted thanks to Plusnet.
The worst part is I was a 4 year customer until we got FTTP and used to recommend them to everyone (worked as IT sysadmin) so now I have to go back to these people and tell them I screwed up and recommend moving over to Zen ASAP.