In this blog post, @rob-hyndman says:
If you only want point forecasts, that is the best approach available in the forecast package. It is also better than any of the commercial software (at least as far as they have been prepared to subject their algorithms to independent testing).
If I follow this same approach and take the average of the prediction intervals produced by both models, will they be reliable?
Update: I've come across with this nice blog post that shows how to create prediction intervals from hybrid models.