I would definitely get modular man... I had a seasonic x750 gold already available. The case is SMALL and I had to carefully organize even the few modular psu cables in order to get the side panel on easily.
Thanks! Unfortunately though hardhead mode is now enabled for me. I enjoy a challenge.
I don't see there being any airflow issues if I play my cards right. I'll let you know how it goes, but my computer won't be completed til a month from now.