Better? If by that you mean "more readable", this is obviously subjective, as I find both ways equally readable, with the goto way looking cleaner to me.
But "better" has many aspects, one of which is speed: the goto way is faster and this is not subjective. This has to do with the fact that the %a variable isn't evaluated over and over with each if statement: it's evaluated only once and then mirc looks for the literal label that matches the content of %a. Considering that this is scripting -not programming-, which means that variable evaluations cost, this way is "smarter", even if the actual speed gain isn't so important in most cases.
