@Francis > There are simply too many on the market to test them all.
Personally, I use the SanDisk Extreme Pro or Corsair Flash Voyager GTX USB drives as both of them have SSD controller chipsets to manage the memory for amazing read/write performance. They are certainly more pricey, but that cost is well worth not waiting around to export music to the device. I have never had problems using either of these drives in any Pioneer DJ unit, both of them with over 10,000 songs.
If you're going to that price point, you may also want to consider the Glyph ATOM, and the Samsung T3, two reasonably small but ridiculously fast mSATA-based SSD drives.