WPT load times vastly different from other speed tests

[kpmcgee73]

Hi,

I've been using your tool for some time, big thanks.

I've just switched over my site to the Genesis framework & theme. My test site on a cheap server is running blisteringly fast measured with WPT: http://www.webpagetest.org/result/151005_TS_C0C/

However my live site, VPS server, Genesis accelerator service is running like a dog measured with WPT:
http://www.webpagetest.org/result/151005_Q4_DSQ/

However load times with Pingdom, GTmetrix, and Dotcom-tools looks ok.

https://www.dotcom-tools.com/DetailView....65BF9FAF:1

Any reason for this big difference, I'm confused which is right.

Thanks
Kevin