Deltec: superb customer service!
Inlet: there is only one and yes, mine is above the sump. I used a flexible tubing to go from the 1.5" drain line into it. I was going to do PVC tubings but was very challenging given the direction of my drain line & the Deltec.
Rolls: yes, super easy to change rolls. I was going through the rolls that shipped with the unit in 2 weeks! I've discover
https://preconfilter.com/ and they can make custom rolls for the Deltec (and other filter rollers) for more than half the cost. The new rolls of 50mu from Precision last more than a month! Talk to Steve @ Precision Converting (super cool guy) and ask for custom sizes for your fleece roller. I've ordered 50yd & 75yd, 50 microns, and the width of 7 1/8 wide (I will do 7 1/4 going fwd though).
You can read more about it from my build thread.
https://www.reef2reef.com/threads/backbay-reef’s-450gal-upgrade.1066683/post-14034250
Overall - I'm super happy with the Deltec Fleece roller!!!
Good luck!