Yep its certainly going to be the most impressive Mainline UK route available for MSTS.
However Making Tracks have never tried to hide the fact that your going to need a beast of a system to run it smoothly. Cetainly the likes of those in favour of EB style routes, arent going to be running Great Eastern at similar frame rates!
I fear that for all the hard work that has gone into this product, they will faulter in the same way Severn Valley did. It might be the best looking route yet, but if people cant run it whats the point?
SVR sales boomed and crashed within 6 months. They still sell in low digits but returns are always related to lacking usablity, or so ive heard.
Hence why Europeanbahn (much to the regret of many) still remain the top selling producer of UK addons...they stuff runs on everything.