If in PWO you mean a stimulant based OTC PWO - I don't and never will. The doses of caffeine alone that some of these formulas have are insultingly too high and I have for years now ceased purchasing any as a result.
I always take a non stimulant based home brew PWO containing l-citrulline (5g), agmatine (1g), beta-alanine (2.5g), taurine (2.5g), KNO3 (1g), Vit. C (.5g), NAC (.5g) chased with 5-10mg of Cialis
I'll have a little coffee for a low dose of caffeine which is more psychological than an efficacious stimulant.
For me the desired benefits are enhanced intra-set recovery, endurance and stamina and a lot less about pump.
Combine that with the anabolic of choice and you can literally go for hours.
That formula actually helps with blood pressure as well.