Having just last month had a most unwelcome happening in the water, I'd like to offer a few insights from the experience.
I won't go into details of why I wound up in the water, but I did (through some stupidity on my part and some unforeseen circumstances not of my own making).
I'm a few years older than you and, while pretty fit, am no athlete. And, I'm about 20lbs overweight. Lifelong sailor, often singlehand, and am very, very careful by nature and by experience.
Nevertheless, one lovely morning I found myself in the water near the stern of my 42' sloop exiting one of the Chesapeake's tributaries. My Mustang 3184 inflatable vest -- which thankfully I was wearing -- inflated instantly, just as it should.
The water was still warm in early fall, so no immediate worry about hypothermia. Note that in colder water this could be a BIG concern, giving you only minutes to survive.
The first problem I noted was that with the PFD inflated I was virtually helpless to do anything useful. Yes, it kept my head above water and was quite comfortable if I lay back in the water. But, it was very hard to maneuver and, once I caught hold of the dingy which had been blown away from me by the propwash of a nearby vessel, I found it was impossible to board the dingy with the lifevest inflated.
My weight, age, physical condition, and state of exhaustion all contributed to the inability to board the inflatable Caribe. Further, I had damaged my right shoulder in the incident, so the right arm was pretty useless. Only once I managed to get my right leg over one of the tubes, but was unable to get any further.
Complicating things, though the weather was lovely and warm, were the factors of wind and current. The wind created quite a chop and the boat was bouncing about. Worse, the current was trying to take me away from the boat, and I had to struggle quite a bit to catch hold of the dingy which was tied to the boat.
I have a top-notch s/s boarding ladder midships on my boat. However, I had failed to deploy it before getting into the dingy and, now, in the water it was absolutely impossible to deploy. Nor did I have sufficient strength left to climb up on the Aires windvane on the stern, certainly not with the PFD inflated.
I briefly considered deflating or discarding the PFD to better allow me to get into the dingy, but quickly discarded the idea as suicidal. In retrospect, that was the right decision...it would have been pure stupidity to do that.
A commercial fishing boat came by after I'd been in the water for about 15 minutes. He tried to haul me out, but couldn't. Not enough strength. I'm a big guy and weigh about 240lbs, but it was impossible, especially in my then state of exhaustion.
Finally, he got a bright idea and lowered a big s/s basket into the water and I was able to climb on it. Then, he caught my dingy and I was able to roll into it from the top of the basket. Once in the dingy, it was easy to deploy the boarding ladder and climb aboard.
Remember, this was all taking place in near ideal conditions, not in inclement weather.
About 25 minutes in the water altogether.
Lessons learned:
1. Never, ever, leave the boat without deploying the boarding ladder.
2. Fashion a means of deploying the boarding ladder from the water. I got a good idea at the Boat Show from the manufacturer of a similar quality ladder, and am going to implement that before sailing again.
3. Fashion a means of entering the dingy from the water, even in an exhausted state. Some sort of deployable ladder, maybe. Try to deflate one of the tubes enough to climb in, maybe.
4. Inflatable PFD's are wonderful, but they greatly restrict your mobility in the water. You need to understand and, if possible, plan for that. My backup plan, had I been unable to hold onto the dingy in the chop and current, was to lay on my back (easy) and paddle toward shallow water as best I could.
5. A handheld, submersible VHF might be a good thing to have along. My cell phone was in my pocket, but was toast.
Hope this helps.
Bill