Wheelbuilding / Wheel Building / Wheel build help

I built a set of wheels on Sputniks using the manufacturer's ERD of 600, calculated with the Wheelpro spoke calculator (though Edd gives the same figures) and the spokes came up too short. I'm not sure if 608 is correct but 600 certainly seemed to be wrong to me.

Ahh, that makes me feel like I've got this right. I was very tempted to just trust the manufacturer like I've done for the past two wheelsets I've built but after seeing Spotter waste 72 spokes and about an entire day I thought I'd measure ERD myself from now on. I'm pleased I did.

Can anyone confirm from experience that I've measured correctly?