Have you seen this video review of the Go Fit Contoured Kettlebell?
Kettlebells have proven themselves to be a fantastic way to achieve the fitness level that many can only dream of! Personally I have been swinging Kettlebells for a number of years. Initially I saw them as a way to work some resistance training into my workouts without having to buy and store a bunch of plate weights.
If you haven't been introduced to them, a great place to start is with the Kettlebell Advantage. It is a great resource to get you started with Kettlebells and it is really a steal at less than $10.