“That’s Where It’s At” is an excellent 1964 Same Cooke record but it was not one of his big hits. I like the version by the Holmes Brothers. Lou Rawls, who had done backing vocals for Cooke and Bobby Womack, who played guitar on the original version, also covered it.
I am not sure if the Sims Twins version (on Cooke’s SAR label) was released before Cooke’s version or not. I am guessing that it was. Johnnie Taylor, who also recorded for SAR, covered it on Stax.