sexual sides are less prevalent with NPP because it is much shorter acting. If you do experience sides you can always stop it and it will be out of your system a hell of a lot faster than deca. As far as joint support, it really depends on how long your cycle is. For just that purpose, 100 mg of deca a week is plenty. For anabolism you'd need 400+/week. You could probably get away with NPP @ 100 mg E3D for joint support.