It's great that you get a good response to Cialis! My urologist told me that a man has to have a total T of at least 600 ng/dL to get a response to oral erectile meds. Maybe that's all you need, along with a more adventurous sex partner.
I'm really at a disadvantage regarding PDE-5 inhibitors. Cialis at low dose gives me a nasty headache that lasts a day to a day and a half. Never tried Viagra. I have Vardenafil and I can reasonably tolerate it, though it messes with my sleep and stomach. Taking a pill would so much easier and convenient than an injection in the penis, LOL. Cialis is the winner since it lasts for 3 days. I read an abstract where men were given 20 mg of Cialis, I believe 3 times a week. Several of them had spontaneous erections return. I can only sadly dream of that.