If you book far in advance then standard class advance NCL - KGX is £77 and the return leg varies from £15-£31.60 depending on which service from the cross you choose. First class is £131 going and between £44-65.40 depending on which service you use to return (prices from EC website for travel in 12 weeks time).
The standard class anytime return is £287 whilst the first anytime return £384.
I actually quite like the livery, I saw it in person yesterday at Doncaster (it was heading south at the time) and to be honest I think EC would do well to convert the rest of the IC225s to having the same livery as it's an improvement to my eye (no need for them all to have the same branding just the colour on the 91/DVT).