i haven't heard either unit, but i'm a flag waving lover of API designs. i really love the sound of that stuff.
i had two RNC's and sold them to a friend. i didn't like them and could never really get them to work for me.
that being said, i'd try to get some demo units of both pres and try em out for yourself.
most dealers will hold a credit card number, ship you the unit (on your dime) and let you check it out. you call em after a few days and tell them you're keeping it, or sending it back (again, on your dime). paying for shipping seems like a really cheap way to demo gear to me.