I second that, been with PN for 5 years, left because they wanted a minimum 18 (reduced to 12 eventually) months tie in.
PN speed was about 1850-2000 download, 450 upload, with my LLU O2 connection I'm getting 3600 down and 960 up, and it works flat out at all times of the day or night.
PN aint bad at all though, I was always happy with the service, but if you have an option to go LLU, DO IT!
plusnet 4/11/2003 -> 4/3/2009
O2 Standard LLU 4/3/2009 -> ???