Hi
Acutally I know quite a few people that applied for both EB1-EA and NIW. Most of them don't post in this forum. I would say that once the cases are accepted (before accepting your case, USCIS officials will look at the case briefly to see if you qualify or not), the chance of having both of your cases approved is pretty high. Overall, more than 80% of I140 applications are approved, and my experience is that the odds for EB1-EA and NIW are even higher.