I *think* (I've never heard it called Radiowave) that they mean the incision will be done by laser. Apparently using the laser reduces bleeding and pain, and makes a cleaner incision. I have considered it for spays, especially for older females, but I've never had any laser surgery done on my pets. I don't know if I would bother with it for a neuter, since the incision is so small anyway, but it might be a good idea since Eddie is an adult. Only $40 more isn't a big deal for a one-time surgery. That is, if "Radiowave" really does refer to laser surgery. If they mean he'd be sterilized by radiation, well, that just sounds scary.
Edit; OK, so I Googled it, and I guess it's different from laser surgery. It sounds pretty good, I might spring for it in this case. Here's a link:
http://www.familyvet.com/radio.htm