I am using a Macbook Pro 15" late 2011 running Yosemite. I purchased the IO Gear (GBU521) for 13.50, ran the activation tool, and then signed out of, then back in to my iCloud account on the MBP, and it works great. Good Luck!
Since I made the post you responded to just now, I purchased said usb adapter. It works well. For some reason, I can't use (consistently) "MacID" app (allows me to log into my MBP, lock screen, wake from lock, auto lock screen when away, (when iPhone is out of range) as well as enter Admin password with Touch ID) while having hand off from iPhone and MBP at the same time. I got both to work at the same time once but, haven't been able to recreate it.
MacID works great when hand off via the dongle isn't in the picture.
For now, I am using Airdrop between my iPhone 6, MBP, and iPad Air. If I need to temporarily use hand off with two of my devices, I can turn hand off on via the settings. I am not using hand off as much as I am MacID at the moment.