schlepporello wrote:...my big question is if the Cerveny's any better since I understand it's supposed to be a Miraphone clone.
A profoundly wrong understanding!
Basically all current designs of rotary tubas are based on original Cerveny designs.
The Miraphone tradition originates in the same area of northern Czechia, where Cerveny was and is seated. Reading the area history from ca. 1936 to 1946 wil tell you why Miraphone, MW, and Glassl are now in Bavaria.
Possibly the only rotary tubas not coming out of the Cerveny tradition were the now discontinued US made pre-WWII ones. One may (very) roughly say, that they were front-action piston tubas with a rotary valve set and a slightly different leadpipe.
Of course newer techniques like ball-and-socket (from the GDR) and mini-ball (from the West) have influenced Cerveny. But as useful these technicalities may be, they are not part of the basic tuba design.
When the question is about piston tubas, then the picture is the opposite. I never liked Czech piston tubas. They may have improved, but in my eyes they still have only one function: to rip-off the low end market in the West.
Klaus
PS: The only two tuba makers producing every single part in-house are Yamaha and Meinl-Weston (according to the owner of MW - after the acquisition of B&S/VMI and building a new piston valve production there). I would have thought, that the same went for Cerveny, albeit on a somewhat simpler level of technology.