I'd like to expand a bit on Jan's otherwise excellent (as usual!) response. While TransEarÃ‚Â® looks like a hearing aid, at that point the similarities end. Hearing aids are acoustic devices, essentially amplifying sounds, which are then transmitted through the ear canal by an acoustic speaker ('receiver' in industry-speak). As we all know, amplified sounds don't exactly help if you have a dead ear!
TransEar was designed specifically for single-sided-deafness, and it is registered with the FDA for that purpose. Instead of an acoustic receiver, TransEar uses a bone vibrator that sits deep in the ear canal of the dead ear where there is only a very thin layer of skin over bone - no soft tissue to dampen the oscillations at all. It is similar to BAHAÃ‚Â® in that sounds are picked up by the microphone, processed by the "processor," then passed to a bone vibrator which directly stimulates the skull. The vibrations are then carried by bone the very short distance to the good ear, where they are processed in a somewhat normal fashion. TransEar is non-surgical, it can be tried/trialed - usually with little or no obligation - like a traditional hearing aid. It is usually fit by audiologists, not surgeons, and once tested and qualified by their audiologist the purchaser can be wearing their TransEar in as little as two weeks. TransEar is usually not covered by insurance, although a few members have reported coverage of some kind. If you search this forum, you will find a large number of posts that mention retail cost, which we have no control over since we are the manufacturer.
Compared to BAHA, TransEar is a relatively new device, in production since late 2005. Like BAHA, we are continually improving the device, so each year it gets better, and we are able to implement new technology to improve gain, sound quality, and reliability. There is still a lot to learn about bone conduction, and we hope that there is a Ph.D. or Au.D researcher out there who has interest in it. I am not aware of any studies that compare BAHA and TransEar, but when you think about it is like comparing an apple and an orange. It is easy to go from a TransEar to a BAHA, but going the other direction probably doesn't happen much once the surgery has been done. This makes it tough on potential researchers.
As Marg has said, it is a very personal decision. The good news is that there are choices from two firms who are committed to their products. And that's a good thing!
I wish you well as you investigate your options. You've come to the right place, as members of this forum prove over and over again how well-informed they are, and how open they are to sharing their experiences.
VP & GM of Ear Technology Corp/TransEar