You might want to order a small qty of each and see which works better. I have fewer side effects with Tadalafil, just a little bit of sinus congestion.
Ordered 90 20mg generic Tadalafil from these folks for US$63 plus shipping.
www.rx-line.com
They are in India, email communication was very good with updates when order received, when shipped, when to expect delivery. Shipped via U.S. Mail to Post Office, arrived in 19 days. I don't have a prescrip, don't recall them asking.
And, they are as effective as the Cialis prescrip I had 10 years ago.