The only con about my CI is not getting it sooner.
At my activation, all human speech sounded like human speech. It was very crisp and clear. Although some people were off in pitch at first, nothing face to face sounded like robots talking.
When I walked into stores with a lot of people talking, at first it was difficult to understand everything that was being said, and that speech had a sort of high pitched quality to it. That's because I hadn't heard well in those environments for quite some time, but after a few months, that went away and all speech and sound quality normalized in those environments.
In quiet, I have no difficulty.
I go to a climbing gym which gets quite busy often. I can have a conversation with 3 other people while we are climbing in a group while everyone is talking and loud music is playing. I can hear my climber shout "coming down" from the top of the rock wall in all that noise while I am belaying. I can also hear stuff going on in all that noise that my friends can't hear, like screwing my carabiner, the sound rope makes while it's moving through my belay device- yet I can still hold a conversation with other people. In fact last night, there were probably 30 or 40 people lined up along the bouldering wall. There were several other people standing around the higher roped climbing walls, people in the weight area, cardio area, etc. I was climbing with 2 other people and in the midst of all that going on I was able to follow conversation about the routes we were trying, what was difficult about them, how they were structured, the moves that would be good to employ, etc.
In restaurants and at large social gatherings I can isolate different people's voices and understand them as well. I have no difficulty moving from one conversation in one place to another conversation going on in a different part of the room when moving around. The sound of utensils, glasses, and plates and other random sounds that you would expect to hear in a restaurant are things that I can hear, but they don't interfere with my ability to participate in conversation either.
In places with a lot of noise, a lot of hearing people ask me to say things again to them because they have more difficulty with the noise than myself. It's like the reverse, instead of me having to ask someone several times to repeat themselves, now I often have to tell my friends when we are in noisy places that they need to go see an audiologist.
At my office, I can hear and understand people talk from their cubicles a good 15-20 feet away from me & behind me, and that includes regular office noise in the background (keyboards, phones, printers, etc). I have the urge to tell them to shut up sometimes because they can be so loud! I think they forget that I can hear them now, lol.
I probably could have been back at work the following week, being able to participate in meetings. I no longer have to depend on a captioned phone, or subtitles on Netflix. I talk on my iPhone and the t-mic allows me to hold my phone up to my ear like anyone else does. It doesn't matter where I am, I can use it in a restaurant, on a busy street, in a supermarket, at home, or hands-free in my car if using bluetooth.
I listen to music through my bluetooth, my iPod, my car stereo, and my computer speakers alone. I have so many options and I can choose whatever set-up I want for music listening depending on how I feel or what I am doing. I hear a great deal of the written music score, not just the main parts. My hearing aids could never detect certain sounds that my implant can. I was happily surprised when I turned on music after my activation, on activation day. It wasn't like it sounded like a fog horn as I heard one person describe it. Although not everything was there, that was due to programming limitations early on. I could tell it was the song that it was, with some instruments and vocals there, and others being missing. I worked with my audiologist on this and over a few weeks we increased my IDR and raised the volume in a few different frequencies, and everything in music that I listened to sounded very balanced and colorful within a month.
Outside, I can hear the birds sing. I can tell that the birds are different kinds based on their vocal patterns. I can hear things going on inside from outside and vice versa. I am able to hear some sounds through glass, which is kind of amazing. I can hear myself wheeze when I am sick. I never knew what that sounded like or what that meant, so it was pointless for the advice nurse to ask if I had any wheezing
when I was feeling sick. Now I know and can answer that question appropriately!
I don't think that I retained any residual hearing after a few months of using my CI. Initially after surgery yes, but the CI became dominant. However, the brain does it's thing and my M levels in the lower frequencies as far as the electrode reaches need to be higher for me, but given that I don't feel that I am missing crucial low frequency information.
I use two smaller batteries during the day because I like the lighter weight, but I also have the option of using disposeable batteries, a larger rechargeable battery, or powering both of my processors on AAA batteries. I enjoy using my completely waterproof one for swimming and whitewater rafting.
. I just hate to see you end up in a situation where you regret your decision. 
