We've got them all over the place, generally with bike lanes, and I use them quite regularly. What I dislike is when I have to climb onto a sidewalk to get to one, but they're generally fine on the street side.

A few streets now have those little diamonds, maybe 1' x 1' for bike specific sensors, which seem to also work without pressing the button. Usually placed at the intersection, so much for catching a bike on the fly (cars often have them 50 or 100 feet before the intersection so it can activate the light cycle before they arrive at the intersection).

I suppose my biggest problem is when I encounter those buttons on the Rosa Parks/Pioneer Parkway median strip MUP. I'd like to go when the traffic gets a green light, and activate them on the roll, say 50 feet before the intersection. But, as it is, to get the crosswalk to activate, I have to stop, push the button, and if I'm late in the cycle, wait for a full light cycle. I sometimes go by the traffic pattern. If I have traffic moving (green lights) on both sides of me, then there is no cross traffic.