I like it better than clip irons (though I'm not sure how it would compare to a good quality marcel handel iron) because the clip is just not there to get in the way of things. And sometimes, at least in my experience, the clip will still leave a little bump in the hair even when just wrapping it around like you would a curling rod.
I guess the biggest thing for me is that it's a great quality tool. It gets way hotter than most curling irons I've used (IMO blows drugstore irons out of the water), gives great versatility and once you get used to using it, is just fab. Though just like xsnowwhite mentioned, you can get the same type of results using a good quality iron, handel or not. I guess it just comes down to a matter of preference
I bought mine on eBay because I couldn't get myself to pay the full MSRP. There are a lot on eBay, at good prices. My only gripe about the iron, or at least the one I have, is that I wish it had a longer cord, and that it would swivel. But I think it's because I have an older version....my iron is not the one pictured in the original post. That one in the picture above are the ones on the website. Those have a longer cord that swivels. Mine does not. But I still love it, and for the price I paid, consider it a great investment
EDIT: So I did some quick research, and quite a few people are saying that the eBay ones are fakes. Personally, I'm really not sure. I think they could be older versions, but I just don't know. Fake or not though, I still love it. It's still far superior to any irons I've used.