You put Eli Manning on our team the past 3 years and you'll see a piss poor QB get boo'd off the field.
Romo has dealt with Dallas drama, poor pass protection, diva receivers, inconsistent defense, and generally an environment not very conducive for a QB to be successful.
Eli on the other hand is in a very QB friendly system where he isn't asked to do anything special, he has a solid defense, good coaching staff, and a team culture built around making sure he doesn't get exposed.
Romo is twice the QB Manning can ever think about being. Don't give me the crap about he has a ring, Dilfer has a ring. Some guys are in put in better situations than others.