Regarding the "claudication", I have a question. When we talk about a 'skin-splitting pump' it's claudication, right? Which then means there's reduced blood flow to the muscle, correct? So let's say you take these OTC vasodilators and blood flow improvers, and assume they work, they should reduce the pump sensation? I personally never noticed anything from NO2 products as far as the pump, and maybe it's because they actually inhibit constriction aka the pump.
I remember "Animal" talking about how you don't want to get pumped as an athlete or bodybuilder, you want improved blood flow for quick recovery between sets, quick removal of waste products etc, and not a pumped constricted muscle.