Convex Circle Mirrors (Blind Spot Mirrors)
Would people with experience buying, using, replacing / removing aftermarket convex circle mirrors (especially on sedans or hatchbacks) chime in here about things like whether they find them useful, which ones to get (or to avoid) and why, and other things that it's good to know about them? I'm thinking of putting them on a sedan's side mirrors, but don't want to cause damage, put them in a bad spot, etc. Also, it seems that there are ones that stick on to the mirror but stick out on a hinge, not just ones that are more like 'normal' stickers--are they better (at least in some circumstances)? I've tried researching them on Google (and here on the forums) and didn't learn much of anything--I may well have missed some obviously helpful website/guide/thread, so if there is one, please let me know.
Thanks in advance for your help!