I have tested a SAW controlled transmitter and superregenerative receiver from the same company.Given that they use the same terminology to describe the outputs of both receivers (i.e. output signal is TTL and can be directly connected to decoder) I am confident that the output of your receiver is digital, as is the output of my test receiver. There is not much you can do with a comparator to reduce the noise. Your best bet is to use the techniques I've recommended repeatedly.