I've got the large Dillon tumbler. I like it because I can tumble 600-800 cases easily. I hold onto empty cases until I have a full batch. I have no complaints - it does a good job. She does make a low rumble, though. It's basically the sound of the cases and media working inside the bowl. If you run it empty, it makes very little noise.
I have had it about 10 years. I have sent it back for service, when the on/ff rocker switch broke. I got it back within a week.
It has a lifetime warranty, but the motor is guaranteed for only a year.