You forgot (float)gameTime.ElapsedGameTime.TotalSeconds at m_rotationAngle calculation:
m_rotationAngle += m_velocity * elapsed;
And then increase your speed values:
const float rotationPerSecond = 250.0f;
const float decayPerSecond = 500.0f;
And it will work both for:
//IsFixedTimeStep = true/false;
//graphics.SynchronizeWithVerticalRetrace = true/false;