I love BevMo for the vast selection, but I don't go here unless I'm specifically looking for something they don't carry in the grocery stores because I typically find Albertson's/Safeway/Fry's prices to be cheaper, at least for common wines.
The staff here is awesome and I love wandering through the aisles looking for weird stuff I've never seen before, but if you're in need of a case of Stella and a bottle of Toasted Head, the grocery store will do just fine!