There is no need to force something iterator style. By all means use a loop if it is more readable. Also, if your iterator style closure body gets very verbose, you can always pull the logic out into a function or closure and pass it in. In the end, both styles are idiomatic, and the best choice is which makes it more readable (subjective of course).

I personally use iterator-style for 1-3 simple ops, but go into a loop for anything more complicated. The functional part of me wants to force iterator style but I fight it for complex use cases because it is irrational on my part, and I find loops easier to read for stuff like that.