A new release of WebPagetest is now available for private instances: https://sites.google.com/a/webpagetest.org/docs/private-instances/releases/webpagetest-2-5
If you are doing any testing with Chrome or Firefox I HIGHLY recommend picking it up. There are a lot of stability fixes that will make testing more reliable.
If you aren’t doing Chrome or Firefox testing then you can still pick it up if you want the few other tweaks but there isn’t a compelling need to.
Thanks,
-Pat