Hehe... I almost posted about these, but didn't think anyone would care. For what it's worth, I got a bunch on clearance as well. The packs I got were half silver, half orange-red - I assume the same you tested.

I hadn't tested outside yet, but in even decent ambient light they didn't show up so well using a decent flashlight.

I also picked up the thumbtack style reflectors... Those seem less useful since the others can be used as twist ties.