Cien Agaves is a great addition to downtown Scottsdale -- and it provides a fun, relaxed atmosphere into the mix of places that either seem to be a) dive-y and dumpy or b) snotty and superficial. Cien Agaves has a cool, open building and has some neat art hanging on the walls.
The margaritas I had here were head and shoulders above the ones I've had at nearly every other Valley establishment (especially at places like Dos Gringos or Salty Senorita).
I came here after work with friends and we ordered a house margarita for $4 (happy hour special). It had a lot of ice in it, but tasted really fresh and packed a punch.
Then I tried one of their more expensive prickly pear margaritas -- yum! Delicious, without being cloyingly sweet.
We didn't get any food, but the chips were great and the two salsas included a pico de gallo and a really amazing green salsa that included tomatillos and, I think, cumin. Great!
The only downside was the service. Our waiter was really nice, but the poor guy seemed completely overworked -- I think they only had one waiter for the entire restaurant and patio. If they hired another one or two servers, the experience would be more enjoyable AND they'd probably move a lot more margaritas! But I definitely plan on coming back here and seeing if maybe that aspect was just an off-night for them.
Try the patio if you can -- it's lovely and it gets you away from the rather loud music that could be playing inside.