I'm in my early seventies and Kamagra works fine for me. I prefer the liquid or gel to the pill, but the pill is ok, too. The gel just gets into the system a bit quicker.
If I take it one hour before I expect the action to start, I can stay hard for about three hours from the start of the action. If there's a lull in proceedings while we take a breather, I might go a bit soft. But as soon as someone rubs it or sucks it, I'm hard again in no time - hard enough for anal, for example. As far as cumming is concerned, I have no difficulty cumming when I want to. These days I can only manage once per session, so I like to hold out to near the end of the meeting. I think Kamagra does make it a bit less likely that you'll have a premature ejaculation (if you're prone to these!), but I don't find it difficult to cum having taken the stuff.
And I'm lucky that I've never suffered any bad side effects, like a bad headache. I think this may be because immediately I've swallowed the gel or pill, I drink a full pint of water, straight down.
As GreyDave says, we're all different and it seems likely that while Kamagra might be fine for some, it also causes problems for others. I'd suggest experimenting with alternatives until you find something that works for you.
