I have been using http://www.linkvendor.com/seo-tools/speedtester.html and think its good. But what others out there that are good?
That tool seems a little slow, and just calculates your server speed from one point which is doesn't tell you. The whole test is strange, not sure what I got out of it?
Google Webmaster Tools has in it a new (under test) speed test. It also has advice on how to correct issues that slow down the page load.
YSlow for me is the only way to go. I use the YSlow Chrome extension and love it. It's easy to use and provides a lot of information and really nice graphs.