At least in my case, the Dr. prescribed 5mg Cialis per day. My insurance only pays for 8 pills per month (regardless of strength) so I got the RX written for 20mg tablets. Bought a pill cutter at the pharmacy. Cut in quarters, that covers the month.
I don't use the Indian pharmacy companies (long story, not related to trust issues, just the customs complications), but I have tried the Tadalafil "Megalis" pills (Cialis equivalent) from ADC with similar results, slightly different side effects, but nothing to complain about.