Comparing ReactiveCocoa with RxSwift

RACVSRX.swift

/* RAC*/
let userNameStrings = userNameTextfield
                     .rac_textSignal()
                     .toSignalProducer()
                     .map { text in text as! String }
        
let passwordStrings = passwordTextfield.rac_textSignal()
                    .toSignalProducer()
                    .map { password in password as! String }
        
let signal = zip(userNameStrings, passwordStrings)

signal.startWithNext { (un, pw) in self.submitButton.enabled = (un.characters.count > 0) && (pw.characters.count > 0) }

//Or ?
userNameTextfield.rac_textSignal()
                     .subscribeNext { _ in  self.userNameTextfield.backgroundColor = self.userNameTextfield.validate() }
 passwordTextfield.rac_textSignal()
                    .subscribeNext { _ in self.passwordTextfield.backgroundColor = self.passwordTextfield.validate() }

/*RxSwift */

nameTextField.rx_text
             .map{ "Hello " + $0 }
            .throttle(0.5, scheduler: MainScheduler.instance)
            .subscribeNext {  self.greetingLabel.text = $0  }
            .addDisposableTo(disposebag)