1.4 petrol with missfire cylinder 1

[andyboy]

a friend in the trade with a diagnostics reader just plugged into my car and it told us it has a missfire on cylinder one, my mate rekons it's a plug or coil?
is one or the other more likely?
i was going to try a set of those bosch super 4 plugs, anybody tried them?

[A2ALI]

Mine has just had a mis-fire fault, they replaced coil no 3!