IMHO a fairing is most useful as a way to beat cold weather. But it does have a few drawbacks. sch already mentioned a few. Another problem (for me anyway) is when there's a strong crosswind the fairing serves as a big sail and it can be difficult to hold a straight line (somewhat dangerous in traffic). Another issue you must consider is if you're using it at night--a headlight shining through the fairing does produce a lot of glare. So you either must live with that, or rig up a way to mount your headlight in front of the fairing. As far as wind in your face, I guess it depends on how you mount your fairing. I usually look over the top of my fairing, so it shields my body but I do get a blast of air (and associated bugs) in my face. But I can lower my head a bit and look through the fairing if desired. Finally, if you travel with your bent, a fairing requires a little more work to transport.