If I were you and I had $250 to drop on a tumbler and supplies, I'd go stainless and skip dealing with vibratory tumblers/disposable media. I've used both methods for several years, and stainless (STM Kit) works much better for me.

Although slightly more labor intensive then vibratory tumbling, stainless steel will get you better than new brass every single time. The only downside I've seen is the added labor of separating the pins from the cases (i.e. dunking them in a water tank), and then having to remove stuck pins from flash holes and case mouths.

I'm somewhat surprised to see what others have posted about it peening the brass. I have never personally had issues with case deformation like others describe, but I've read of 2-3 others on various forums claim it damaged their brass.

Keep in mind though, with a vibratory tumbler, you're still going to have to clean primer pockets, and it won't ever get the inside of the case clean. I always found them messy as well.