Just a heads up for anyone buying for the UK. The Tag Managers appear NOT to work if you use Virgin Media as your ISP and use there Cable router in normal mode. However if you supply your own Router and place the Virgin Media Hub in Modem mode only, then Take Manager works perfectly.
Clearly something to do with the DHCP server that is built into their router or how it dealing with certain ports perhaps (regardless if the firewall is on or not.)
Jonathan