Research chems are funny like that. I've been using Maxim's Tada for about 1 1/2 years without an issue. My opinion is that most users of Tada don't really understand what it's actions are and therefore claim products are no good when they are actually fine. Tada will not make you want sex, does not effect sex drive or over come any mental hang ups you may have with sex. It only induces proper blood flow to your junk so you can get and keep an erection if you're properly stimulated. That's it, nothing more nothing less. If your girl isn't turning you on or that donkey porn site is boring you then Tada won't help. It won't fix issues with your junk due to estro or prolactin complications either.
I have a script for Cialis and to get the same effect as 20mg of pharma I run .50 ml (1/2) cc ED which is 15mg per the label. Here's the rub, I run it ED for the other benefits so I'm pretty well saturated at .5 ml ED. If was only using it every now and then I'd probably go 1ml (30mg) or maybe 1.25ml to get the same effect as a 20mg pharma tab.