1. Variations in response using licensed ED generics are often more likely to be due to how you're feeling. It relaxes muscles that allow increased blood supply to cock, not causing it. You're more likely to be turned on by some women than others for instance, or before your first pop rather than afterwards. I would guess that Viagra, although considered the best for hard-ons by users (in studies, not just on here) might be less effective than Cialis for second pop as it metabolised faster. I will use it on that basis as it's kind of a better hypothesis than no hypothesis, and it seems to work, but there might be a placebo effect there too, so "it works for me" isn't proof.
2. Headaches - Sudafed can be better than simple painkillers as it also deals with sinus problems caused by dehydration, common with some EDs (especially Cialis IMO).
3. Can I remind people only pass on or post info on licensed UK suppliers unless it is to a close trusted friend. Legal generic manufacturers abroad get hassled every day by big pharmas, who will probably monitor sites like UKP. As they have no legal recourse against them they just complain to the merchant services and get their crefit card licenses removed. It is ruthless and cut throat. Another big, completely legal generics manufacturer had its credit card facilities removed recently due to a simple "mistake" by the punter.
4. Gels are great for faster assimilation if you can hold the gel under your tongue till it dissolves (faster absorbed than in the stomach). However they are a bit messier to take, usually s bit more expensive and generally more available from non uk suppliers. Sachets I've had a slightly smaller than a credit card so it's easier to store one in your wallet than a tablet. Just some thoughts.