There are many offers for ovens like this, by many companies, they all look somewhat similiar and maby even come from the same factories in Asia, but they differ in very small details. The big window in the Mayer versus small windows in others - or none in most. Many or only few slits in the rim of the upper lid (do never shut them with aluminium foil like some did, because not few people saw their thermostate or heating elements being destroyed by doing so). General manufacturing quality, loose versus fixed heating bars...
Obviously I cannot say anything on longevity of the device, but so far it all looks very encouraging. Absolutely recommended by this one brand at least.
https://www.amazon.de/Mayer-Barbecue...4400858&sr=8-2
It comes with a teflon pan that can replace the stone, and two peels that work very practical (half-moons in form).
I am considering buying a second as reserve. I just love it.