One of the top 2 feeders preferred by my Hummers!  I have over 50 Hummers and have several types of feeders out for them.  This is one of their favorites, hands down.  The only problem I have is that is a bear pulls one off the window (we live in the woods near the Canadian border), the perches or the plastic fingers get broken.  The easy answer to that is a piece of copper wire wrapped around the screw at the bottom that comes around to the back and then through the holes and folded outward.  For the perches, you can do the same thing making little loops of copper wire that fasten to the screw on the bottom.  I have more then 10 of these feeders.  All but the two most recent have some sort of copper wire fix and most are more than 6 years old.  Just ordered 2 more to hang on the fence line.