Hi Brian,
My AN was 2.5 by the time it was discovered in July 2007. Amazingly, I was essentially symptom free (other than minor hearing loss that I had astutely attributed to other people not speaking clearly enough) until around March 2007, then suddenly the symptoms began to emerge. Due to its size, I needed to be treated and I saw several doctors and did a bunch of internet research to decide whether to have surgery, GK or CK. I detail all of this, and how I came to my decision to go with CK, in my website below (in my signature line).
When I went in for CK, basically what I was told is that my symptoms were very unlikely to get worse, there was a reasonable chance that they would improve, and there was a reasonable chance that the symptoms I had on the day of treatment would remain. In other words, I had to be prepared to live with my symptoms as they existed on the day of treatment. At the time of my treatment, I had some very minor hearing loss, some numbness around my right lip, and dizzy spells. As it happens, my hearing has remained unchanged, the numbness has gone away and the dizziness has greatly subsided to the point where it does not significantly impact my life or the activities I'm capable of participating in. There were months of very bumpy patches, but I'm now doing fine. (The "post-treatment" section of my site recounts my progression after CK treatment.)
I'm of two minds about W&W. On the one hand, I think it makes a lot of sense to delay the trauma of treatment as long as possible and just enjoy life as it is. But on the other hand, your pre-treatment symptoms may impact your post-treatment quality of life, and delay in treatment may result in the onset of new pre-treatment symptoms. After all, most people W&W until they become symptomatic. There is also the risk of continued, irreversible deterioration in hearing.
I raise these issues as things you should explore carefully with your doctors. My main suggestion is go see a few neurosurgeons now--preferably ones trained in both surgery and GK/CK, so you get all perspectives on treatments and your current situation. I agree too that perhaps deciding on a treatment now might help take a load off.
Best wishes,
Francesco