Having a mobo tray that slides out in the sub-$60 market is very unlikely.
The XClio case is a solid one, it has more cable management than the Antec 300 as with the A300 you have the PSU at the bottom and most cables aren't long enough to reach up the back of the board (no holes cut anyway!) and over the top (once again no hole there either).
I would buy the XClio for the money, it offers great cooling and is pretty flexible, seems to be a good buy and
take into account the free shipping.