WPT load times vastly different from other speed tests

Support
1

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 good, see below:

https://www.dotcom-tools.com/DetailView.aspx?id=5682ECB5BFAB4783943D56BF65BF9FAF:1

I’ve always used WPT as my default. But I’m very confused why the big load time difference and why my current site seems to suck with WPT.

Thanks
Kevin

2

GTmetrix is showing my homepage loading very fast: https://gtmetrix.com/reports/www.vintageheirloom.com/uMga60BS

I hoped this was a temp glitch with the testing server but I’m still getting really slow load times: http://www.webpagetest.org/result/151005_SH_JYY/

Aaggh, confused.