Well as it turns out, Gandalf has an even louder murmur. Apparently that entire litter of kittens had heart issues. I'm starting to think that Waby may have had a "Patent Ductus Arteriosus" issue that killed him when he was only 18 days old.
As it turns out, Fluffys Neuter went off without a hitch. Gandalf had a wild heart arythmia start after his operation began, with his heart rate varying from 80 to 150. We finished his operation quickly and he recovered fine, but if this had been a Spay operation (if he had been a girl cat instead of a boy) we might have lost him under anesthesia. As it was I just finished with him under as little anesthesia as possible.
When I get the chance, I want to have the ultrasound doctor look at him. That scared me.