Datakit has a good translator
Expensive but worth the money when you don`t have to remodel. Works like a charm except for some reason it has trouble with simple flat surfaces occasionally. The other pain to consider is that it takes some coordination with the Catia user to get models that come over as separate solids. Without a little prep work you usually get one big grouped nurbs set and when you ungroup, you have a zillion little surfaces to pick through and rejoin. Even with these little annoyances, I think it is still worth it.