I've fired a Mateba too, more recently than the Webley-Fosbery, but for some reason I remember it less distinctly than the Fosbery. It was more like firing an ordinary heavy revolver. We had the 357 Magnum version, but we only had one box of Magnum ammunition. We decided to put in the 38 Special recoil spring (that's a feature of the gun) but that wound up taking forever, and that is what I remember most. We really ought to have left the 357 Magnum spring in; there is more point to having such a big, complex revolver for a really powerful cartridge than for something as mild as 38 Special +P.
In short, it's a nice gun, but not as unusual as the Fosbery. I think the recoil stroke is shorter because it uses a conventional hand-and-ratchet than the Fosbery's cam-and-track system. And it's a swing-out cylinder, not a top-break. It's just not as different.