I have them. Not too great. Fairly cheaply made. For example, it took me almost an hour to push the laces through the eye holes which are simply punched through the layers of the material.
Not particularly supportive, but I'm used to Nike squat shoes, which are very well made.
They are better than socks or slippers but not by a lot. The soles are pretty good.
They are fine for competition over a slipper but you won't add anything to your pull.
I like pulling in my Nike Romaleos.
Not terribly relevant, but I have the SABO GYM shoes which I pull in and they're pretty much the cat's whiskers.
Have been thinking of getting the deadlift shoes, but really, the GYMs are bang on for everything. Only shoes on the market that has less than 0.75" heel, and which also hasn't been discontinued.
Great customer service, too.
For the record, I agree with Tom. For most lifters, I advocate pulling in a heeled weightlifting shoe. I personally save the flats for meet prep and meets, since my wonky anthropometry means I can lock out significantly more weight that way. But for general training, and for the vast majority of lifters, I'm an advocate of pulling in weightlifting shoes.
Jordan pulling 705 in socks was kinda cool, though.
I deadlift in my socks and have found that I can consistently lift more weight, than compared with my weight lifting shoes.
The lack of any heel height in the former is immediately obvious to me when lifting.
If I could find a shoes with minimal sole, effectively just an arch support, that would be great.