I do think that regular masturbation is good in case tou have PFS (generally speaking). I do know that for most of you it is dificult to get or even maintain an erection when masturbating. Have you tried to use a lubricant with hot effect? Since we have less desire, our own lubricant is not working any more as it should. Then, to use an external lubricant (what you can find in any sex shop) will make your masturbations more comfortable.
Give it a try and comment. For me, i can feel the diference.