Yes, you are right, there are a number of people on whom our cialis acts worse than cialis from the pharmacy, or does not work at all (but there are much fewer such cases). But for most, it works.Cialis didn't worked for me at all. I thought it could be underdosed and then took 20mg, still didn't do a thing. I tried 10mg of pharma next day and it kicked in 30 minutes, so...
On the other hand their sildenafil works like a charm, exactly like the pharma. Sick boners, a little red face and congested nose if you go more than 1/3 of the pill.
Maybe there's something on the excipients or the coating as manzo said that prevent absorption for myself. I didn't bothered to send it for testing because i'm positive it will turn out legit, never saw a bad testing of driada, but for me personally cialis is like i didn't take it at all.
So far, we have not been able to get an answer from chemists about what the reason might be. Perhaps the reason is really in the shell, but this applies, as you correctly noted, only to tadalafil. Sildenafil always works at 100%