Originally Posted by signupdamnit

It's like asking how long a piece of string is. Some work, some don't. Of the ones which work they may not work in your particular case depending on certain factors like placement and the materials which will be blocking them. Placement and the antenna will mean a lot. You may want to go directional. It would be better to run a ethernet cable if you can to that floor and place a separate router there. If not and you don't know much about this then call someone who really knows what they are doing in order to get the best results with the least hassle.