Johnmak,
Not everyone wants a firm keybed, and the keybed is not what dictates whether or not the keyboard is professional or not. It's what comes out of the keyboard that determines the overall quality.
Now, some folks, primarily those who were piano players, and sometimes, accordion player, in the past. They often utilize the key pressure to develop some sort of expression to their playing, which is good thing. Others, such as myself, could care less about weighted or semi-weighted keys because we are sitting down at the keyboard 5 to 7 days a week, often several hours a day, and playing to live audiences, which in itself is very demanding on both our minds and bodies. After just an hour of performing with a weighted keybed, my hands begin to cramp. A couple nights behind fully weighted keys and I have to soak my hands in hot, salted water to kill the pain. For me, those lightweight keys were the best thing since sliced bread.
Now, as you stated, the sounds provided by the S-970, and the S-950 are incredible, and the styles are absolutely outstanding, which is the two main reasons to purchase any arranger keyboard. While there are hundreds of other onboard features available in most keyboard, the vast majority of them are rarely used by players, both home and pro, which never ceased to amaze me.
Good luck on whatever you decide upon,
Gary
