I've tried all three under a few different circumstances. I'm 50, 5'9", weigh 175lbs, and am in great shape physically if that matters here. The times that I've tried these meds have all been within the past 5 years.
The Viagra is kind of shorter in duration, and on occasion will seem to desensitize me a bit. Sometimes that is OK, sometimes not. It does produce rock hard erections though. Sometimes I stay hard after cumming, but if I don't, it's still not really soft or limp. Following rounds are less pleasurable for me, and I take longer to orgasm.
Cialis is supposedly a longer duration kind of a thing, but for me at least, it really didn't seem to have much of an effect. Granted, I'm not really having any issues with ED at all, so maybe it did help a little with later rounds, or the next day, but I didn't really notice anything all that different.
Levitra is my favorite. About 30 to 60 minutes after taking it, I get a warm, flushed feeling in my face, so I know it's working. It gives me that rock hardness, but still allows me to enjoy the full range of sensations for whatever we're doing. It may slightly delay orgasm, but not much if at all. I do find that I'll go flacid for a while, but returning to a full, throbbing erection is effortless, and this continues for hours for me. I've even felt that it helped the next-morning, wake-up nookie. The Cialis gave me absolutely no after effects, but both the Viagra (half of a 100mg tab) and Levitra (20 mg tab) gave me headaches. Nothing too intense, but noticable.
Hope that helps. ;-)
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