[jabl]

It ought to be safer since the fission products are encased in the protective and non-corroding triso structure. That being said, used LWR fuel rods are also enclosed in protective cylinders (see eg the designs for the Finnish Onkalo storage site). Both safe enough per current best knowledge.

If one wants to do some fancier recycling and reprocessing rather than once through, I understand this is relatively undeveloped.