Does anybody have cellular (honeycomb) window shades?

Tweet

I recently discovered that there are window shades called cellular shades or honeycomb shades that supposedly help to buffer outside noise. They are also energy efficient, because they filter sunlight out and help insulate the window from outside heat or cold. I'm thinking about buying some for my home. Anybody who has these type of shades in their home/office, could you please tell me if they've helped cut down on outside noise? Noise buffering would be my main reason for buying these type of shades, so that is what I'm most curious about. They are a bit expensive, so I'd like to know if it would be worth the investment. Thanks in advance to all who respond.