My melodicas get a lot of use. I take one with myself on almost every gig - just in case. I also carry a melodica to all jam sessions, and to parties where there's a chance I could play a few happy notes. I've got many different brand/models, so I almost fall in the "collector" category. My favourite is the Yamaha brand (the azure one, in particular, but I digress).
This pipe/mouthpiece fits Yamaha melodicas. I bought it several times, because when the pipe gets dirty with accumulated condensation, it is quite hard to clean without leaving it with an unpleasant soap/solvent smell. Sugary drinks (wine and beer in particular!), micro-particles of food, simple saliva acids, all these things contribute to soil and partially clog the pipe.
The Thomann replacement is almost as good as the Yamaha original, except for the tube mouthpiece and the angle of connection to the melodica body,
The mouthpiece feels "softer" if your embouchure is tight and uses teeth pressure (as when low notes or sharp attacks are needed). This is not a problem for me.
The angle of the pipe/melodica connection is straight, while it is angled (approx. 90 degrees) on the original Yamaha pipe. I prefer the angled joint because the pipe doesn't go flailing around as much. Definitely not a serious issue, though.
The standalone mouthpiece is much like the original. I put one replacement in my melodica gig bag every time I go out, just in case.