This is a largely pointless post, and yet, I feel I have to make it. I joined the Slicehost world about 4-5 months ago, and am nearing the end of my prepaid subscription. I just want to say, for anyone considering signing up, that I consider this to be the best hosting experience I have ever had. I have had 0 performance or connectivity problems, 0 downtime, and not a hiccup to complain about. Uptime is at 126 days and counting since I finished all of the initial setup/testing, and I have YET to ever run into the disk performance problems that I was constantly experiencing elsewhere.
(This is on a 512 slice running nginx/PHP-FastCGI/apache/Postfix/amavisd-new/cyrus-imapd and the usual ssh/ftp/etc. services with 3 low-traffic sites + email for about 50 users.)