I can't comment much on Cirrus aircraft as I've never flown one, however, I'd be concerned about flying any aircraft that hasn't been tested in a spin? I may have got it wrong and it has been, and is just "not cleared for spinning" like many others ... Surely as most will recover if needs be, advising the use of a chute in such circumstances seems odd? That said, I accept that the chances of getting into a spin in such an aircraft is the smallest risk of danger over the other possibles such as loss of control in IMC.
The account of the water landing is dramatic and very interesting to read. The ellow is obviously intelligent and full of survival spirit. Having a brain seizure must be very scary (even more so in flight) so I'm sure he did what his confused brain told him was correct at the time. If it hadn't been for that though, I'd say to pull a chute having successfully recovered to controlled flight was crazy! the aeroplane may very well have been structurally compromised, but if the wings were still attached and everything worked, a landing would be the only sensible option IMHO.
SS