I have had both good and bad experiences with Walmart. They sold me an upside down catfish as a small pleco when he was only MAYBE 1" long. He's healthy and happy, even with bouncing around to different tanks due to my current tank juggling. HOWEVER, I went back and got two more since the price was so good and they both died within 48 hours (and gave six of my female bettas ick in the process!). I've had tiger barbs from there that lasted less than 24 hours, but I've known people who have gotten livebearers there and they still have them three years later. I honestly trust the Walmart near me that sells fish more than my LFSs at this point. Both of my LFSs have filthy tanks and I've seen diseased and dead fish lying in the tanks with no effort made to treat or remove them.
But, I agree with what lauraf said. Use your gift card to buy supplies and get your fish at a trusted LFS.
But, I agree with what lauraf said. Use your gift card to buy supplies and get your fish at a trusted LFS.