High Speed Scores, low site speed

Good Afternoon all,
I have recently moved an eCommerce site to woo-commerce. I have cut down the site file size, and ran alot of optimization including w3 total cache. On gtmetrix and pingdom I get a page load speed of 2-3 seconds. However, when I try to load the page, it often takes 7 or 8 seconds before I see anything. The webpage is boat.net.nz, any insight would be appreciated.