I'm trying to decide between the Festool 574422 DF 700 XL EQ Plus and the Festool 574447 DF 700 XL EQ Plus. ??? What's the difference?

These two tools are identical.The 574422 just comes with the Domino XL Joiner.The 574447 comes with the Domino XL Joiner plus it includes the cross stop and trim stop. These accessories are also available separately. However, this set offers them at a discount versus buying separately. The cross stop is helpful for repeating mortise along a long edge. The trim stop is made to help with placing mortises in thinner stock.