Asics works its logo into a cleverly designed night safety light with four red LEDs. The $15 Hi-Res LED uses powerful neodymium magnets to secure to any garment. So, like the Snapalite, you can put it anywhere on your clothing for high visibility and ease of use. Both the Snapalite and Asics weigh about half an ounce.
But do the magnets hold on tight? We placed an ordinary running shell between the magnets and the backing, and unless you shook very hard (harder than would occur in normal running), it stayed on. But while putting on a thick fleece jacket and straightening it, the Asics would fall to the ground.
Points for the Asics: A reflective surface when the light is off; better looking; magnets are probably gentler than plastic clips for sensitive fabrics.
Points for the Snapalite: Brighter LED; stronger attachment to thick garments; on/off switch can be operated while still attached to a jacket; can be lashed to a bike with included strap.