By guessing/estimating, I'd say the Feisar Prototype has a top speed of 130/100 units from the ship selection menu. That is some pretty ridiculous speed. Before I made level 50, I was anxious to unlock the Piranha Prototype, thinking it'll be even faster. It isn't. It's probably 110/100 units.

On another topic, which is slightly related, why are the Protype ship stats inaccurate? Every stat is at 50 except for the ship's specialty. It's odd that all the standard ships have accurately labeled stats except the prototypes.