Summary: Only stick-on heatsinks I've ever bought that didn't fall off eventually. Everything about these is great, from the quality of the heatsink itself, to the thermal pads, and heck even the packaging is top notch.
Pros: Great heatsinks. I bought these to cool the VRM chips on my motherboard. They do the job well. The thermal adhesive on these is the best I've ever seen, hands down.
Summary: If only they came with taller heights like that of the full length VRM solutions for specific boards such as the MST-66/88. The dimensions however were an exact fit for the VRM clusters on a Gigabyte 880GMA-USB3 v3.1 motherboard.
Pros: - Adheres strongly without coming off providing the surface areas are properly cleaned prior to application and then heat cycled after.
Cons: None that I can foresee really. They are heatsinks and serve the purpose compared to not having them in the first place.
Summary: I got several packages of these for memory and VRM cooling on my 2 HD4870s when I moved them to water cooling. They definitely move a lot of heat, you can feel them getting warm when they cards are under load. My cards used to suffer crashes related to overheated VRMS, but they have been completely solid since the upgrade. I was also happy that these taller version ram sinks fit under my water block's barbs without needing to bend the fins out of the way.
Pros: Economical, can be used in a variety of places, very sturdy hold with the default thermal tape, but gives you the option of removing them later (compared to thermal epoxy). They seem quite effective at sucking heat off of whatever they're attached to.
Summary: Fits perfectly in the router, fit perfect in between my two 5770s in crossfire (put these on the bottom card). Will probably be buying more just to have on hand.
Pros: Solidly built, as to expected with forged copper. Tape is pretty sticky, I haven't had any fall off. I'm using 4 of these to cool the radio cards and cpu on a NETGEAR WNDR3300 router, along with a 60mm fan. Keeps them from overheating/dropping off. I used the other 4 on my video card RAM, and it seems to be doing well there also (Not that I had any problems before.) Great product for the price.
Cons: Wish there were more to a package (10-12) but hey, I knew what I was buying, and it's not dropping an egg for it.
Pros: Does what they're supposed to do - keeps VRM's nice and cool. Used them to replace an aging backplate/thermal pads on my HD 4850. They were easy to apply, stuck great, and fixed the artifacting I was having.
Cons: Smaller than they look in the pictures, but rest assured they fit even large VRM's just fine.
Summary: I used them on microcontrollers for an ambient lighting system with LEDs - each chip is pushing a few amps out to 600 LEDs, so I went a little overboard on cooling to protect the board. These worked nicely.
Pros: The tape is pretty sticky, so you won't really have to worry about them coming off. They're made of copper and they get rid of heat.