I moved from Plusnet FTTC to Zen a month ago, and couldn't be happier.
I have the same 80/20 sync. (obviously), and get a little better results on a speedtest (1Meg up/down perhaps). But for browsing/general internet usage goes, it's been a bigger improvement than the move from O2 ADSL to Plusnet FTTC!
My Broadband Ping
Not having the wife/kids moan about the internet is worth the money alone.