Can't provide any good comparisons to similarly priced products (system took a lot of leaps vs. baby steps), but I do have a Stealth, and actually sent to to Jerry replace mine with one at current standards (MkII) a couple weeks back, and spoke to him today to find that the new unit is getting shipped back today...
I was extremely impressed by the changes provided to my system across the board...which I hated, part because of cost, and part because it was hard to imagine such changes from such a lightweight, relatively boring little black box that you plug things into.
Its a happy and upsetting moment when things that transform sound end up in my system.. I'm happy because things end up the way I want them. I'm upset because I know its that much harder for me to pull them out of the system, and thus the financial investment stays. There's only been three components in my system that have really done this for me -- the Audio Magic Stealth, the Audio Consulting Silver Rock, and the Acoustic Reality EAR2. Other items may have come close with fun factor, but those are the three I continually have trouble parting with.
Again, this won't help you with comparisons, but you'll get my endorsement, that's for sure.
I know a lot of AA and Audiogon folks have done comparisons, so you may want to search there if you haven't already.