Very happy with these cages. As far as function, they work as well as any other good cage I've used; which is to say they hold on to water bottles securely.
What makes these special is the finish and the lightness. The matte finish on these cages is very, very nice. It's uniform throughout and is a great match to a matte carbon frame. And my particular cages weighed in at 24g, 2g under the claimed weight.
Only real con is the price. $100 for two bottle cages is admittedly steep, but worth it to me.