I have played Special 20s and Crossovers for years, so I decided to try the Rocket. Out of the box, the reeds were gapped too high, so I had to immediately adjust them. After adjustment, it plays extremely well. It is very responsive, crisp, and loud like a Crossover.
The comb has a different shape from the Special 20. The holes seem bigger and the surface is shaped differently. I personally do not like the shape of the Rocket comb. With the bigger holes, it seems harder to play with accuracy.
The Rocket is a good harp, but in the end, I don't prefer it over Hohner's Crossover and Special 20.