Are you planning on doing your own install? If so you might also consider ease of installation. Some are easier than others. Do a search here on the "Bolt" on IFS and get some ideas from those that have gone through this experience. After investigating this I decided on Heidts and have no complaints.
You asked what + and - there are. I know of no negatives; however those that favor stock restorations will chime in on that point.
