I'm a fan of AD2, but taking the upgrade last May, gave me 3 kits, then Black Friday Sales led me to invest in the 4 I was most interested in. At the moment I keep talking myself into the 3 I would add, but not being 100% I then chill on the idea. Hoping that they release something new that's helps make my mind up They say more is on the way.
I agree with the OP, even as an AD2 interested user, two versions providing a connection with it is enough. I fear they release something later in the year, and I will hold off buying them because next years sonar will bundle again. Puts you between a rock and a hard place.
If I had more Rock sensibilities, it wouldn't be such an issue.