Another question that needs to be asked, do you want the caller to be able to cancel the request? Using `-replay` prevents that.

> Is that typical of a networking layer? To start the request immediately?

It goes back to the question of cold vs hot. Cold signals are generally preferred, they compose better and as I said, their subscriptions are cancelable. In fact, replay operators and `RACReplaySubject` are tentatively planned to be [deprecated](https://github.com/ReactiveCocoa/ReactiveCocoa/pull/877) in RAC 3.0.