I love my Exp 3.0!! I got it "gently used" which may mean that any bugs were repaired. Came with all the warranty, lessons and extra feet, etc. - just like new!
I also heard negatives about the 4.0, but maybe that has been solved, too. Only reason I'd like a 4.0 is for the knee-lift foot and the low bobbin alert!
Maybe you could find a good used one.