It's pretty cool, especially all the effects included. You can sample any sound and resample with various effects to come up with some really crazy sounds, and it even has a vocoder, and you can record with it...
Second hand Yamaha A3000 are very good value. I bought one 6 months ago and can recommend it. Make sure it has v2.0, because it's hard to find upgrades.
He also asked for the best HARDWARE sampler. I've never gone wrong with Akai samplers so I recommend any of their samplers. But then it all depends on what you want to do with it, some samplers have features that others may not have etc...
akai is the kinda standard sampler on the market... the others have other more weird features that some might find useless, others totally cool...
e-mu though, makes the best ones imo... more capacity of everything...