Paid (weeks before my transfer date) a year's line rental in advance to move to Plusnet. All went well until, at the start of the second month, they started charging me for line rental (which I'd already paid).
It is well-nigh impossible to get through on either their phone or chat lines and they refuse to give an e-mail address. To stop them double-charging me I had to cancel my debit. Shortly after that they first messed up then totally cut off my service and it took 4 days of constantly hanging on the phone listening to their deafeningly loud muzak (and 4 of their agents) before I got one who could actually sort out the issue (instead of simply saying it was sorted).
I contacted their CEO (andy.baker@plus.net) to complain but no-one at Plusnet would accept that their systems are seriously flawed or that their customer service is unacceptably bad.
Eventually my contract came to an end but Plusnet even messed up my transfer out, putting a cease order on my line which took 3 weeks to resolve. During that time I had to pay Plusnet's extortionate 'no contract' price to keep my connection alive.
When the service was working the connection speed was very good (for my line).