I did it a few years ago and never got a trial. I was called once but was dismissed. They initially call fifteen and three are rejected; I believe this in case any of them are deemed unsuitable for some reason (e.g. known to the defendant). I lived quite close to the defendant, so I suspect this may have been the reason.
When I was initially called, we were stood on the stairs for ages, waiting. We were then told the court had adjourned and we were to return after lunch. When we were called back, we were waiting again, until eventually being called into the courtroom. After they selected the jury, the three of us who had been rejected had to stay for the indictment.
The defendant was a respectable looking man - I'm guessing late 50s, / early 60s. When the indictments were read out, he accused of about five counts of 'indecent assault on a minor under the age of 14, between the date of XXX and XXX' (different date ranges for each count). The victim had the same surname, so I'm guessing he was the grandfather.
When I returned to the waiting room, I remember thinking about how I would have felt if I had to listen to the evidence. Part of me felt I would be distressing, but part of me felt I would like the opportunity to ensure justice was done.
I saw a few of the jurors who had been called. The trial had ended very quickly. They said it was clearly a stitch-up; they reckoned there was a family feud and this was an attempt at revenge. If true, it seems pretty sick to drag a young girl into such a sordid plot.
I do agree that juries can be flawed, if you get a few retards on them, but I don't think there is much in the way of an alternative. I think there is a case for certain cases (such as complex financial crimes) to be heard by a panel of judges, or perhaps some sort of 'expert jurors'. I don't like the idea of other cases being heard by judges or professional jurors - I don't think the former would be impartial, and the latter would probably result in twelve Norris Coles deciding your fate.