The performance of the Amel Super Maramu, Amel 54, and Amel 50 varies based on several factors such as sailing conditions, sail plan, and equipment.

In terms of speed, the Amel Super Maramu has a maximum speed of around 9 knots, while the Amel 54 and Amel 50 have a maximum speed of around 10 knots. However, top speed is not the only factor that affects performance.

The Amel Super Maramu is known for its reliability and ease of handling in rough seas due to its ketch rig and bow thruster. It is designed to be a comfortable bluewater cruiser rather than a high-performance racing yacht. It has a displacement of 16 tonnes and a waterline length of 12.3 meters.

The Amel 54 is a modern design that features a sleeker hull shape, larger sail plan, and more modern equipment. It has a displacement of 17.8 tonnes and a waterline length of 14.7 meters. It is designed to be more of a performance cruiser than the Super Maramu, with a higher aspect ratio sail plan and a taller rig.

The Amel 50 is the newest model of the three and features a similar hull shape to the Amel 54 but with a shorter length and less displacement. It has a displacement of 15 tonnes and a waterline length of 13.3 meters. It is designed to be a comfortable and easy-to-handle cruiser with a self-tacking jib and electric winches.

Overall, the performance differences between these three models may not be significant enough to make a significant difference in terms of cruising speed or overall performance. Instead, the choice between them may depend more on personal preferences, budget, and intended use.