Cons: The metal components are connected together by plastic.
Nothing prevents the metal pieces from spinning in opposite directions and breaking the connecting wire.
I ordered a dozen to connect Unbalanced audio output into some amplifiers I own that only have 1/4 balanced inputs.
After about 18 plug/unplug the internal wire between the two pieces breaks and then adapter no longer works reliably. The RCA connector can spin in the opposite direction of the 1/4 jack.
I ordered many cables and fittings from Mono-Price and the total cost of my order was less than the cost of 1 -12 foot cable at a local merchant. I have purchased from this company before and have always been satisfied. They have the best prices of any that I have researched
Pros: As long as this does what you need and expect, it's the usual Monoprice quality. Its sole use in any conventional equipment is to connect a mono source to a 1/4" stereo input hack.
Cons: It probably won't do what you need. It can not be used in any differential TRS jack, either input or output. It can't (shouldn't, anyway) be used on the output side of any stereo amplifier or preamp because it will short the stereo outputs together.
The problem with this is that Monoprice did not see fit to describe the internal connections. Turns out that the T and R are internally connected to the center conductor of the RCA jack. There aren't too many uses of this configuration, far as I can see, plus it has the added disadvantage of defeating any use as differential TRS. I'm downrating it not because of its manufacturing, but because of the lack of full description on the product page here.