Very interesting discussion...[Sorry, not an i12s owner, but I look to learn from all re-entry/PFD discussions]
My recent experience was with my first ever inflatable PFD that I wear on hot days because it is cooler than a noninflatable PFD. When my sailing kayak capsizes it turns turtle so my first surprise was the PFD automatically inflated under the boat -- I thought it was manually operated! Disconcerting, but not a problem.
The second surprise was that because the buoyancy of my inflatable PFD is located largely around the neck/upper chest, I was lower in the water than with my normal sailing (not inflatable) PFD, so the opposite rail or fins was much harder to reach to right the kayak. Reaching was also made much more difficult by the frontal bulge of the PFD.
The third surprise came when I tried to use my normal method of vaulting over the stern (like getting out of a pool) to get back on the kayak. (I weigh nearly 80 kilograms and my kayak is rated to 102 kilograms). Because I was lower in the water at the start and because of the PFD bulge out front, I had to start the vault further away from the kayak, so it was a lot harder to get up onto the kayak. Yes, I could have deflated the PFD but that kind of defeats the purpose of having a PFD. (I also have a paddle float).
I still wear the inflatable PFD (converted to manual activation) when it is hot and I am in sheltered waters. But to deal with the shortcomings of the inflatable PFD, I have installed the
kayak rescue step. This is a very neat package and it works as a throw rope as well.
When I am in open sea or the water is cold, I wear my sailing PFD, a Zhik dinghy one that has all round buoyancy. I don't like the idea of a thin back to a PFD because it means too much padding out front. My recent experience has made me realise how much I was using the buoyancy of my sailing PFD to bob up and down in the water to get momentum for a vault/lunge.