Fran,
I own both a Sd-1 Ketron and a G70. The build quality and key feel is outstanding on both. I do have the Sd-1 for sale and after a mid April gig the G70 is going on the block. They are both too heavy for this guy. I am an organ player and key feel means squat to me. I know Don M. feels the same way as do many others here.
Tom