What are some alternatives?
GTmetrix - GTmetrix is a free tool that analyzes your page's speed performance. Using PageSpeed and YSlow, GTmetrix generates scores for your pages and offers actionable recommendations on how to fix them.
HttpWatch - HttpWatch: The ultimate HTTP Sniffer for Chrome, IE and iOS
XRebel - XRebel is a lightweight Java profiler that helps developers find and fix common problems in their application as they code.
WebPagetest - Run a free website speed test from multiple locations around the globe using real browsers...