Love it! Just bought the plus membership for $20 more (I average at least $40 in cash back with this one per year so it made sense for $20.) We have managed to use a Groupon discount for Sams for the last 3 years now. The trick is to rotate the primary member. Me one year, my husband the next year, etc.
Weird. Cuz when I did it through Living Social (I did mine there, got the regular membership for $20 and then got a $10 e-gift card back), my local Sam's already had a list of people who had signed up for the deal.