It's just as different as acceleration and top speed are from each other. Your original suggestion would spit out acceleration, mine spits out top speed.
And yeah, @ThreeCubed, shape is a factor, particularly in turning rate. Shape technically only affects the stokeslet drag (basically, viscous shear within the water due to the lack of slip between the microbe's surface and the water around it), since no matter how a microbe is shaped, it will displace just as much water when it moves. I'm not sure how large the stokeslet drag is in practice though, so I can't say whether shape makes a big difference for linear motion.