i know the cuttlebug can take all the other dies, you just need adapters/spacers, not sure about the others. The cricut actually works on cartridges and will only take its own brand, it also doesn't emboss. Just to confuse you even more, Kaszazz has just released their own cutting machine the "bellish", which I think would be better than the cuttlebug as it is larger and I am pretty sure you can cut 12inch papers on it, the cuttlebug cuts about an A5 size.
Also, if i was to ever get another cricut, I would get the larger size, again to be able to cut the larger size.