Worthless on my 2 vehicles
Wouldn't stick on my 2 vehicle ('95 4runner and 2000 Jetta), maybe because of the curved windshield. Bought the bean bag and am very happy with that. It's the way to go IMHO. You can than hide it when you leave the car leaving no telltale apparatus to tempt thieves.

Not quite an identical replacement...
I ordered a replacement for my suction-cup and A/C adapter in hopes that it would fix the periodic power-losses I am seeing with my Nuvi 660. I had my previous cable strung underneath my dashboard and up to the lower left-hand corner of my windshield which resulted in just a little bit of slack. However, when I went to replace the cable, I found that the A/C adapter cable that comes with this product is about 6 inches shorter than the stock cable that came with my Nuvi. It's not long enough to work with my current configuration...and I will now have to find an alternate means of mounting my Nuvi.

Falling Off
After 8 months of using it (removing and reattaching) to my windshield, it starting to keep on falling off the windshield of my 2004 Toyota Sienna. It seems to be happening similar to the original suction cup that came with my NUVI 660.

Garmin GPS Adapter
I wanted an adapter for my second vehicle. It worked as well as the original.

a good option
This has proven to be an excellent option. It is convienent and works perfectly. As I am using it in a small roadster, I do wish it had a coiled cord.