Stephen - I would encourage you to read the recent thread entitled "Andrew Phillips". He was a local RV7A pilot and was flying along with two other local RV pilots from the same point of origin to the same destination. He went down for reasons yet to be determined. There was not one peep on the radio from him - his flying buddies were close enough that they would have heard him keying the mic even if he didn't have time to transmit any voice. As it was, there was nothing on the radio. Nothing. He just disappeared without providing any alert to his flying companions.
Your idea of being in radio contact is great, but it does nothing to help you in the event of some of the most common aviation incidents: pilot incapacitation, CFIT, mid-air collision etc. The idea behind an ELT is that it transmits even when you can't. You're personally not sold on ELT's - I hope you don't have to have a bad experience occur to you or a loved one before you change your mind.
By the way - there have been quite a few posts on here about trying to hide the ugly ELT antenna under the aft empennage fairing. This idea, from a Search and Rescue standpoint, is an absolute non-starter. The aircraft mentioned above had its ELT antenna mounted under the fairing and it couldn't be heard by SAR until the search aircraft was directly over the wreckage. As a result the ELT was of very limited use in the SAR effort. Compromising the installation makes poor ELT operation a foregone conclusion. The mounting requirements for ELT antennas on the exterior of the fuselage aren't recommended idly by the TSO - there's a darned good reason for these installation requirements.
Oh, one other point... Everybody talks about SPOT being a saviour. This incident aircraft also had SPOT on board and the two RV buddies flew back to its last reported SPOT breadcrumb. The incident happened mid-afternoon and the wreckage wasn't found until after 10:00pm. So much for a SPOT being able to help you get rescued in short order.
Bottom line is ELT's are a required piece of equipment in our airplanes for very, very good reasons. You're building an airplane that'll be worth at least $50K, and your backside might even be worth something, too, even if it means only that your body is found so your spouse can get an insurance cheque in a timely manner. As the old saying goes, if ya got a 10 dollar head, wear a 10 dollar hat. If you figure you're worth something, whether dead or alive, the investment in an ELT is worth every penny.
As for the 406ELT's themselves, I have an ME406 in my aircraft, and have installed several Kannad units in certified airplanes. Artex now offers a relatively cheap GPS interface for the ME406 which will allow our handheld GPS units to transmit position data to the ELT. That's a real game changer. On the other hand I've installed several Kannad units. They are easier to install and offer a little more intuitive user interface.