There's quite a few good Android tablets for under $300. You have choices based on what matters to you.
I prefer the N7 because of the screen (viewing angles are great) and it's a Nexus device (more updates). I got the 32gb so I don't think I would need an expandable memory slot.
So it really depends on your wants and needs.
Here's a list of tablets so you can decide. I'd suggest to stick with Acer, Asus, Moto and Toshiba when buying a tablet. That's strictly my opinion though.