I have a vibrator tumbler a 25 year Dillon to be exact. Do you need to pay top dollar for it to last twenty years? Probably not but I liked the size and color and well it has keep running for 25 years. My guess i other brands have lasted 25 years plus too. Thus it boils down to size, price and make that you want. Bottom line no matter which one you pick it will clean brass.
Dust? Heck yes there is dust. However it is not being tossed up into the air invading every little nook and cranny when it is operating. This just doesn't happen on one that have a rubber seal on the lid.
Now when you dump to separate the brand form the media yes there is going to be dust. Not much mind you but still there is dust, it usually just falls on the floor but I suppose some may get suspended in the air. I found using a dry sheet when cleaning my brass cuts way back on any dist.
Polish? You know just about anything will work. I use the Dillon stuff, car wax you name it and it works.
How Long? That is a good question. Sometimes the brass cleans in as little as an hour sometimes three. However the more brass you have in the tumbler the faster it cleans.
Are they quiet? The right answer is well no! Some my make less sounds but in general they make a little sound. Now the amount of sound is clearly dependent on the users adaption to constant sound. To me I have not found a tumbler that is a distraction.
A nice thing about my tumbler it works for small amounts and large amounts. It is nice to have the capacity to do large amounts of brass if needed.
Should I go wet or dry? Strictly a personal preference however many people will always be sure to try to prove to you why they went either way as being the best.
Just remember your cleaning brass not building a rocket. All methods works and if one is better than the other I doubt you would notice.
The nice thing is you have a lot of choice for something so simple.