this is my fist disposal I've ever had not to mention installing it for the first time.
however, the easy instruction that came with made it very easy with my new sink that i purchased the same time, so made it even more convenient to install with the sink out. and when i turned it on for the first time i couldn't really hear much noise coming from the disposal. so i thought it don't work oh no. so i put some oranges in it and turned it on with some water running through it...and lo and behold it works great and its very surprisingly quiet unit. we love it. :)