My impression from interviewing at both: both are freestanding children's hospitals. CHOP is very academic, CHLA is not as academic/research-focused. CHOP pays residents a decent salary compared to COL, CHLA does not. CHOP is a bigger program and has more resources. Other than that, it comes down to a lot of subjective things. I liked CHOP more than CHLA but that's not to say that you will feel the same.