I think they're doing just fine. The stock MMG's review base (there are hundred and hundreds of them to read) is legendary, and as far as the other speakers up the chain, they are always well reviewed. I believe Magnepan was given Speaker of the Decade recently by, I believe Stereophile..
They know what they're doing, and it gives the aftermarket guys room to do their thing. That's how I ended up with my beauties. I loved the MMG so much I dropped many times over what I paid for them into mods and now have high performing (beyond stock) small room planars that look like heirloom pieces of furniture.
I was lucky enough that Hypex came out with their super high performance Ncore amps and now also have nearly 500 watts per side. And they eat it up, by the way.