Costco has reported impressive financial results, beating earnings per share (EPS) expectations and showing a same-store sales (SSS) increase of 6.9%. The company's margins have also improved better than expected, and it boasts a 90.5% worldwide membership renewal rate and a 92.9% renewal rate in the US and Canada. Analysts, including Roth Capital Partners' Bill Kirk, acknowledge that Costco is 'universally loved' and continues to gain market share. Despite its strong sales, some analysts caution that the stock's high valuation leaves little room for error.