The vibrating bullet is housed at the very tip of this toy; if you look closely, you can see it in the pictures listed on this site. The vibrations stay very close to the bullet, so you don't need to worry about your fingers going numb while gripping the bottom of the toy. I would say, the vibrations are barely noticeable at the middle of the toy and down.
The controls are very easy to use, just turn the dial up or down depending on what level of vibration you need. The dial turns on/up clockwise, while the battery compartment is opened by turning it counter-clockwise. It takes a little bit of effort to open the battery compartment, so you don't need to worry about accidentally opening it.
This toy is so quiet, it won't be heard under the covers. If you, like me, use toys without any covers, you won't need to worry about it being heard through the door.
This toy does not look waterproof at all - no o-ring to keep out the water, so don't test it in the shower and be very careful about getting water on the controls.