As for SongMaster Pro, the performance I got from it, as I mentioned, was pitiful. You can't expect glowing customer reviews if a product produces gaping holes in the seperated bass stem, even if the source audio is compressed. I've worked on software product development and you have to do your requisite homework to be successful as determined by the marketplace.
This is not a fair statement. I don't have Studio One 7 to test, but I'm 300% sure that it will also fail to separate bass (or any other track) sooner or later, just like any other similar program in the market. Try maybe a 1940s old jazz tune, a Cuban song recorded with a baby bass, a funky song mixing lots of slap bass notes with fingerstyle, an 80s tune with a doubled synth bass, or maybe a 60s song with a tic-tac bass line extremely panned to the right (let alone flamenco, modern Indian / African music and other world music styles) and you'll probably see by yourself.
Would you say then that Studio One performance is pitful? You shouldn't, at this stage of development, this is simply how these algorithms work, they have been trained on certain types of material and they are designed to work well in most cases, but they cannot be expected to work perfectly well in any possible scenario.