Alyson 1 and Alyson 2 have different proportions in the arms, and a slightly different posture. As a result, they don't have the same joint parameters. The grouping between the two versions is also slightly different. What this basically means is that conforming clothing will not work the same from one version to the next.

This is what made the conversion rather tricky. The best compromise was to figure out a way to get the basic GNDA shape applied to Alyson 1 WITHOUT changing her proportions. Otherwise it would have meant totally rerigging her. Not a pleasant prospect. 8-)

Given the choice between the two, I'd lean toward making conformers for the Alyson 2/Poser 9/Poser Pro 2012 version because of the improved bending with weight maps, the better proportions, and the other nice features that P9/PP2012 has to offer.

Dynamics would probably work between the two, but conformers and poses will differ because of the different JPs.