My recommendation: Using an SD card is fine for most project, but you can now use a USB drive to boot your Raspberry Pi. So, if you try to use your Raspberry Pi as your main computer, or for a project where the disk space matters, I highly recommended using an SD drive.
Strong points: The model I recommend is not the cheaper, but its performances are awesome, it’s built it in a solid waterproof case and the USB cable is included. Also, it’s then SanDisk brand, so you know I like it for this reason 🙂
Alternative: If you are on a budget, you can find alternatives with lower storage capacity and pricing, it’ll not compete with the SanDisk model, but it would be better than your SD card. Get some suggestions here (link to Amazon) for the cheapest models available right now.