I've started using post image and I've looked at a couple of others.
One thing I liked about Photobucket was that it had a logical url for your image, e.g. http// phobucket.com/username/folder name/sub folder name/your image name. If you are like me and label your image title-01.jpg, image title-02.jpg etc , when doing a post with a lot of images you could simply past 1 url over and over and edit the last bit. The 3 alternatives I've looked all insert a random string of numbers somewhere in the url which means you can't do this. You have to copy/paste each post individual link . Whilsit this isn't a big deal, and certainily not worth $400 USD, PB's system was definitely better that regard.
I can't say I was ever bothered with speed/adds either as I only ever hot linked from there, and after all it was free.
Still to cut of the service with no warning is poor and a shame for all those old builds linked back over the various forums. I certainly won't be going back and fixing any of mine