hmmmm.... Thermarest doesn't show the product on their website:

https://www.thermarest.com/

... I should say, they don't show the product for me. The site uses cookies and may have identified me as being American and not shown me products they sell in other countries. I note your link is for the UK. Multinational conglomerate companies can often give different market footprints to different parts of the company in different localities. Perhaps they want Thermarest to compete in larger campground camping tents in Europe or the UK (...or maybe some other market and this tent just found its way onto Amazon.uk) and let MSR compete for lighter tents.