Hey Steve, I think you'll be very happy with the basement sump, I know I am. Probably the greatest improvement I've ever made to my tank. Most of the noise goes with the sump, and I don't have to get on my knees to work on it. Plus, I can have a large make up water container and water changes are much easier since I can pump the new water into my sump instead of carrying buckets. Also, my temps stay cooler in the summer. All in all, the only negative is out of sight, out of mind. I'm down there almost every day though. I think your pump selection is good, I didn't look at the pump curve, but it seems like you'll just make your target. Probably wouldn't hurt to slightly oversize if it's right on the edge, you may want to add reactors later, or decide you need a little more flow through the sump.