I completely agree with ryshark on the not needing a refugium nowadays. I've seen a couple discussions online about how you could accomplish the desired effects of a refugium, just by having a sump with a really good protein skimmer for starters, and then the sump would also make it easier for you to use media reactors, calcium reactors, etc..
I still prefer the use of a fuge... i think it's a cool way to bring water quality up, and still have something fun to look at while it grows out. Plus the benefits of having tons of pods
and any other critters you want to try to harvest lol. If i had a bigger tank, or a bigger place to put a bigger tank to use as a sump, i would definitely make one section for a protein skimmer and any other reactors i could think of, and then one section for a BIG refugium. Almost like a second tank haha. That's my dream sump lol.
Anyways, i think either one you choose would be good, just as long as you use one. There are benefits in both.