If you want to buy them for the reflectivity, you'd do better to buy tires with reflective sidewalls, or to apply reflective tape to your current rim. The reflectivity of the Halo rims is kind of underwhelming.

Light coming from an angle:



Lit from straight on:



From 20 ft away:



The further from the light source, the more weakly the Halo reflects compared to decently retro-reflective tape. Even from across the apartment, the tape on the fork is noticeably brighter. The rim is better than nothing, but there're cheaper and more effective ways to light up your bike.