Buying brandless aftermarket parts for your motorcycle is always a gamble. The good news is, they are generally pretty cheap. The bad news is, they’re generally pretty cheap.
A little naked roadster motorcycle’s looks are generally improved, to my eye, with a mirror replacement. Bar-end mirrors as a whole are a gamble, though, since they can radically compromise rearward visibility.
Replacement is generally pretty easy if you have traditional open-end handlebars. Removing the stock bar ends is as easy as loosening a Phillips screw and pulling out the bar end. The bar ends, and then the mirrors, are held in place with a large-ish rubber grommet or two. The bolt that holds the bar-end on goes through the rubber and there’s a nut on the other side.

I see a lot of product reviews that complain that the product, whether an aftermarket bar-end weight or mirror, does not fit correctly, or the bolt head just spins. You must make sure the bolt and nut are just tight enough that the expanding rubber piece gives some resistance and the nut doesn’t turn inside the bar. Slide that part in and then tighten the bolt end with a screwdriver. If it spins freely without getting noticeably tighter, pull the end out, finger-tighten the nut on the end and reinstall. If installation is proving tricky, you can lubricate the rubber with something like soapy water, or tire lube (Ruglyde) if you have it around, or perhaps a little hair spray, if you work quickly. It is the friction that holds the part in place, so you don’t want anything that will remain permanently slippery: any kind of petroleum-based grease is right out.
While installing the cheap mirrors was a breeze, their functionality leaves something to be desired. The form factor is what it is, and we’ll see, when the snow melts and I get the bike out on the road, if I can see anything behind me at all. That won’t change whether I spend three times as much on the mirrors or not. Also the adjustability is tough; the ball of the arm is very tight in the socket of the mirror. I can see that loosening up with a bit of use, so better too tight than too loose!

The big problem is, and it's hard to capture in a photo, but there’s a divot right in the middle of the mirrored surface of one of them. This might be a show-stopper. The question remains, though–do I return them and see if another set just like them is any better? Or do I suck it up and call it a learning experience? What if the optics of the mirror surfaces are so bad I can’t see anything even if my elbows don’t take up the whole mirror?
One thing is for sure: no matter how you acquire it, education is generally expensive.