.... I feel AB is more advanced technology wise... I mean, ClearVoice? Waterproof CI, better protection of the internal device (it can tolerate up to 6 joules, whereas Med-El and cochlear are between 1-3 joules), only 25% capacity of the internal device is being used, so it still has 75% more to go for further upgrades/advancements (Med-El is about 50%, while Cochlear is just about maxed out capacity wise with no further room for further technological advances, they'd have to come up with a whole new internal device with more room for such advancements), etc. And keep in mind with Cochlear, it's not wise to SWIM with their device on. Has to be still clean water, only up to 3 feet for half an hour, which doesn't even compare to the Neptune. And as for Med-El's longer electrode array, it really doesn't make that much difference sound-wise.
All three companies are going to do what they can to keep up with the technology, but I felt AB was further ahead than the other 2 myself.
Check out cochlear implant HELP
and see the stats on the different devices.
The way I see it, Cochlear keeps coming up with new processors (with some improvements), they came up with the N5 internal implant but it's pretty much the same package as the N24 (just thinner and different shaped), but they haven't done much to improve speech processing strategies (and have been focusing a lot of their attention on the BAHA's from my understanding). I don't know much about Med-El as I don't pay as much attention to them. AB, they're always working away to improve EVERYTHING, processor design, new speech processing strategies, and are even currently working on a newer, smaller BTE processor rumored to be released 1-2 years from now.
All 3 implants do get the job done either way. It just depends on what you want most from the implant as each device will have their pros and cons.