Hi there! Actually, I have had fusion done on several occasions. The plus side to it is that it looks totally natural since it's blended in with your own hair. Also, you have a little more flexibility with it than you would with traditional weaves. The negatives? It can pull your hair out if it isn't taken out correctly. Also, it takes quite a bit of time to take out the glue. Like, you will have already removed the hair, but it's like the glue is having such a good time in your hair that it just doesn't want to leave the party. The last time I had it done, my hairdresser at the time kinda jacked me up by attaching the hair with too much glue. When I took them out, my hair was coming out with the glue, and there wasn't much that I could do about it. If you have it done, make sure that the person who does it knows knows KNOWS what they are doing, and also (before you get them put in), see if you can have them remove it when the time comes. They put it in there, they should know how to take them out.
There is a version called Great Lengths (I think their address is
www.greatlengths.net), and that's supposed to be less or not damaging to the hair. However, only selected salons provide this service. Their website should have a locator, so you can see if there's one near you. They are so not cheap, though, so be prepared to spend some dough!!
Hope this helps. Have a great day!!