I've been wanting an SSR for a while now, will probably pick one up sometime in the not-too-distant future. In my case I was thinking more in temrs of IDPA competition, which is why it was made. The SSR division of IDPA is pretty much dominated by, and was essentially designed for, K frames like the 19/66.
As far as considering it for a carry gun is concerned, if you're okay with a gun of that size for carry (and if the 29 works, the SSR surely will), then it's a go. OTOH, I wonder whether a 4" 686 might not be a little better with the one extra chamber, or even a 627 (or 327) which holds 8 rounds. In a carry gun we want every advantage we can get.