I've read a few shootouts between the top selling aerators and the results are always mixed. In the end it's just an expensive gadget.
I have the Vinturi (got in a white elephant gift exchange and NOBODY stole it) and I'd say it's more hassle than it's worth. The only real value to it is when you're already drunk and laughing at the duck quack sounds it makes. But by then you're not tasting the wine anyway.