SFSpeechRecognitionRequest

I'm looking at the SFSpeechRecognitionRequest object but it's saying not to use it, and instead use SFSpeechAudioBufferRecognitionRequest: https://developer.apple.com/documentation/speech/sfspeechrecognitionrequest

I want to work with the contextualStrings but I'm not seeing that as an option in the other objects. Do I ignore this warning and use it anyway?