I signed up for a month of the CS512-UK package based on the thread:
http://www.webhostingtalk.com/showthread.php?t=764011
Its unmanaged and I opted not to pay the extra for Cpanel - it comes with HyperVM and you can install LXadmin from there, or even install Webmin or ISPconfig yourself I guess.
I screwed up the application form a bit as its not very clear, but a quick Email sorted that out and within 30mins I had my SSH login and IP for my server. Any Emails I sent since got replied to within minutes - quicker than the online support thing.
Anyway, it only took me a few hours to get an Ubuntu 8.04 LTS Server install up and running with POP3(S), IMAP(S), webmail, SSL, MySQL etc; so I really didn't need the control panel.
I'm glad I went with the 512Mb guaranteed, 1Gb burstable instead of the 256Mb I was looking at elsewhere, as I was using 400Mb+ before I disabled ClamAV, now I'm still using around the 360Mb mark, mainly filtering bloody spam!
I'm very happy with the service and performance so signed up for a year upfront - with a further discount, and migrated all my domains across. Just waiting for reverse-DNS now, which seems to be taking a while, but it could be propagation delays i guess.
I was looking at my WordPress stats and the VPS does the SQL queries in a quarter of the time my old Sun Netra did at the colo, plus I don't have the nightmare of driving down to Docklands to replace a disk or whatever, after two years of having a colo I'd rather leave that to someone else!
I was also very impressed with the HyperVM serial console - i.e. you can SSH into the host and get to your VPS even if you've screwed up the firewall rules or accidently turned off SSH passwords before uploading your key (ahem!)
Network speed-wise I downloaded a tarball at 1MB/sec which is as fast as my 8Mbps ADSL will go.
So very happy overall, my only complaint could be it only includes one IP address and adding an extra one adds 15% onto the monthly cost, but I guess its just me being a Scrooge!