I have a Cuttlebug (manual die cutter and embosser) and a Silhouette (electronic digital cutter). Both get used, but the Cuttlebug far more. They have different uses - each has its place on my desk, and I wouldn't be without either of them.
For any manual die cutting/embossing machine you will need dies (which can't be resized in the same way that the Cricut can resize its shapes) and embossing folders, which of course cost and need to be stored the same as Cricut cartridges do.
One good thing is that nearly all dies and folders from other companies will fit the Big Shot. I think there are a few dies which are too big for it - you'll have to check the sizes - but not enough to worry about.
I say go for it and have fun!