This truly do work as it should, as I haven’t had any problems with it personally. I’ve been using it for the past few days and I’ve been able to use numerous Pokestops and fight in various gyms (being from Michigan, I even slowly made a “jump” to Canada and put pokemon in a gym there).
I actually log in and out since I let my friend use my device to spoof the location as well and haven’t ran into any problems (except when he apparently was experiencing some issues like others listed with not being able to catch pokemon or get items from Pokestops). When problems arose, all it took me was rebooting my device and voila, it was working like a charm again.
So if anyone is experiencing problems, do try closing both the LocationFaker and PokemonGo apps from multitasking and respring/reboot your device. Thank you to the OP for this share.
NOTE: You have to spoof your location realistically. No city, state, or country hopping from your initial position otherwise you may get blacklisted quickly (or suffer from not being able to catch Pokemon or use Pokestops). This has been said before, but just want to remind those who don't take the previous warnings. Don't blame the OP if you were not responsible with this exploit.