Red Tempest with Regular crew without flux hits a decent 400. With Elite it's around 425. It is faster than any fighter too, making it an awesome anti-fighter ship.
This is without augmented engines BTW, and general in system speed is 540 with the 100% boost (more outrunning of everything)
It also has: 0.1 flux shielding efficiency, around 500 flux dissipation, which is enough to fire both beams with the shield up and stay at 0 flux (in other words, soft flux doesn't exist) it can take a hit of 7500 kinetic to the shield and not be overloaded.