Commercial Member at both. RD has more choices in both grade and cut of meat. If you compare the prices of the same cut/grade they are fairly comparable in Atlanta. Next comes the convience factor. I have a upscale Sam's Club (Brookhaven store) right next to my office and I have one about 15 minutes away from the house. RD is about 15 minutes away from the office (I have two RD options about the same distance as there are 3 in Atlanta). But then I'm in Atlanta traffic. 90% of the time, it's Sam's Club for me unless I'm looking for a certain cut and grade of meat that only RD has. Hell, one time I was going to smoke a whole beef clod, and ended up settling for a chuck roll from Sam's (smaller and similar cut). RD had the clod and the chuck rolls, but Sam's only carries the chuck rolls for their large primal cuts. RD for monster beef ribs also!!!!
We were buying for events at RD, but the local Sam's was pretty much even on price so with it next to the office, it had a big plus and we generally get office event supplies (coffee, cups, drinks, aluminum pans, chips, crackers, nuts, etc...) from the Sam's Club.
But if you have access to both, it's nice to have options...