Mega Ride Boot Fit

Your Scarpa 28 is actually a 27.5. But almost equal to a Garmont 28. This is how it gets confusing, but essentially every boot maker is different.

A 28 Mega is a 320mm sole length, which I imagine is close to your Scarpa's sole length. Ignore "sizes" and go for fit and try to keep it near the sole length that works for you.

thanks all, after continued research without being able to actually try one on have gone ahead and purchased a pair of 28's online, with a 100% customer satisfaction return policy.
Anyone interested in new last years boots there is a good sale at backcountry.com's outlet section of their website.
this boot was $314 with free shipping.