I'd be interested in how they work in 180gr fired from a 308Win. According to Knowledge Base Ballistics Studies the slower speed of the 308Win is actually good for the 180gr SST.
Like Mike said. If you're stepping up that high in weight, I would look at the ELD-M line as well. With the 178, you should be low enough MV to take any shot with that as you would with the SST. The extra BC will extend your range if that matters.
