Dataset of one, but I've been more and more impressed with Target's online offerings lately. I've gotten a little sick of the fakes/third party nonsense on Amazon so I tried both Walmart and Target. As long as you're ordering over $35, Target does free two-day shipping, and they've been pretty seamless for me.
Target has been doing this for a while now, via their acquisition of Shipt.
Target started by adapting their supply chain to leverage underperforming brick & mortar stores as distribution centers, which is great. But they really need to up their e-commerce game. The website itself makes product discovery much harder than it should be, and their selection is still far inferior to Amazon & Walmart.