The max operating voltage is 4V, so the 3.3V supply will be fine, however the Arduino can't supply that kind of current. You will need a seperate voltage supply. One motor can draw up to 430mA. Multiply that by 4 or 5 and that is a lot of current. Also the motors will probably be pretty noisy, so it would be better to seperate the motors' and Arduino power supplies.
The data sheet only spec's 'typical' numbers. I don't think there is any way to gurantee the motors rise and fall times will be consistent without verifying each motor you use.
An N-channel FET should work well. Connect the Arduino pin to the gate, usually through a resistor (100 to 1K), but it's probably not necessary. Connect the motor between the power supply (3V or 3.3V) and the drain of the FET and connect the source of the FET to your common ground. Both power supplies must be connected to the same ground.
You want a resistor (10K or more) between the gate and the source to make sure the FET is off when the Arduino pin is not configured as an output (such as in reset).
Almost any N channel FET will work for you. Look at the rated current. Any logoic level FET rated for at least 1A (2A or more would be better) should be fine.
Steve