Nope not street legal. The thinking is that the average schmo will not check his bolts often enough and lose the ring.
Ugly?
This has got to be one of the sexiest looking wheel out there!
Followed closely by this one:
Champion makes some good looking versions using A/R wheels as the starting point.
But yes this might be a sensible alternative. Do you run very low pressure? I guess before you spend the money on something you have to determine how much you really need it. I have not heard of many X owners throwing a bead.