How long does the effect lasts? Viagra, Cialis etc

based on your experience which of these drugs has the most long lasting effect?
I know V should last a few hours but for me, once in a while I try it (i didn’t care much about empty stomach…), it lasts until next day, C lasts for about 4-5 days, what it does depends on?
I still have to know/understand what is the effect these drugs do on the human body, I mean, I don’t know how they work…
are there other doing same effect as V and C?

thanks

DG

Cialis gives me muscle cramps and aches mostly in my legs for two days that’s why I don’t take it anymore. Viagra pretty much is in and out of my system in 6-8 hours with no body pains. The only thing I miss with the cialis are that it works so long and gave me a great flaccid for days.