ME might have a heritage, but surely the likes of Rab and Montane have greater claim to be today's "definitive British mountain shell jacket brand"? Surely Berghaus would have something to say about this rather tenuous claim as well?
Rab/Montane's eVent-powered Latoks and Superflys had this market cornered long before Pro Shell came along, and probably better too. It's also hard to ignore the great products coming out of places like Crux for the upper end of the market.
Outside those who treat Trail gear tests as gospel and/or consider Gaynor Sports to be the best kit shop in the Lakes, I can't believe many people still lust after ME as their ultimate kit. Perfectly solid but not in the same league as the above brands, let alone the foreign alternatives.
I will give you Rab but not the other two. I think Montane used to be good, but recently they have let their game slip. I think eVent is a fantastic fabric but in some recent jackets Montane have not put it together very well IMHO into a good fitting product. Berghaus was the first big name brand to become a fashion item for city dwelling chavs. In recent years TNF has taken over where they left off. Today, rightly or wrongly I see Berghaus as a bit of a stale yesteryear post-chav brand. TNF is pretty much a matured chav brand now.
As far as ME is concerned I think they make premium products for outdoor wear and the products are well designed, fit well, innovative, stylish and you want to buy and wear them.
I think the new Polartec NeoShell fabric is a bit of a game changer because it is adding more competition to the market which I welcome. That means everyone has to step their game up now or they fall by the wayside.
I think Mountain Equipment and Rab are the two league leaders IMHO with ME probably #1.