That will be fine. It’s not concise, but here’s a thread with some supporting info;
Basically, the only time someone might see an issue is if they were a) using a 4-molex cable into a single PSU SATA/PATA port or b) not using all four molex connectors on the midplate. So, spreading the load across the four molexes and two SATA connectors on the PSU, you’re fine.