This Dynamic Spectrum Mapper is a pretty crazy device after having watched the videos! Will have to try. I'm wary of "fix-all" devices (vocal rider et al). At the least, as a de-esser, DSM seems very powerful and as new/diff. as it seems to be, definitely warrants a good working over. Considering the source it can't be easily dismissed.
As for the SW compressors, I've grown to love the Alpha comp in a mastering context, for numerous reasons. Sidechain HP control is often crucial. M/S dynamics are extremely helpful when dealing nasty transients-snares, harsh vocals for ex. Parallel mix capability is major. It does nice-and-easy, and crushing, equally well. Up and down compression, too. The oversampling continues to surprise when picking up gain, pre-brickwall.
Much as I'd like to ditch (and do when I can) brickwall, it's comforting to get good average volumes up w/out having to rely on the limiter.
As for SW limiters I tend to go with the UA Precision for more open, acoustic work, the Pro-L for more dense applications.
Highly recommended, the Alpha comp, though it takes some time to get comfortable with, imo.