TubeNet

I am also interested in those horns you mentioned. Test playing in a shop, I found them both really good but a bit different, the rotary version gave me a more open feel and was a tad louder, (my impression when playing in a little test cabin). The piston model is easier to control for fast and high playing imho. I am looking forward, perhaps I can get the two horns for some days testing at home, but this will not be before end of march. If this happens, there will be a report.

Gerd

I like feel of the piston horn more: really great horn for a really great price.
The pistons on the one I test played made a bit too much noise for my liking. The only thing I don't like about it is that the first vlave slide is a bit hard to access comfortably.

....that test cabin was so small, I don't want to give too much credit to the feedback there.
These horns are constructed to give an easy high register response and are not comparable to bigger orchestral contrabasses, but they are not small tubas anyway. Someone described it as a "Bb tuba with an Eb heart". If you want something to have a really big tone in the low register, may be this is not the right thing.

Gerd