Never heard of Pro Viagra as such. If you mean to say generic Viagra,then
1] Both generic and brand Viagra gives same effect, both differ in price. Generic Viagra is cheap while brand is costly.
2] You require prescription for brand Viagra while generic doesn't require prescription.
3] Generic Viagra has more chance of showing side effect, 비아그라 구입처 while brand has less because you acquire Viagra prescription once doctor recommend you based on your health for brand Viagra.