I think it boils down to how much effort and $$$ you want to spend. A well made acrylic sump won't be cheap but it can be plug and play. Someone else has figured out the refugia space, chem chamber, bubble traps, etc. All you need to do drop in a skimmer and you can quickly be in business.
On the other hand, you can go get a used 55 gallon tank for a song and build out all of the above with some silicon, egg crate and spare plastic. It's not hard at all but will take an afternoon or two.
My sump is a DIY made of plywood with pond liner. It's gigantic which is exactly the way I want it. Everything fits inside it with room to spare. This allows me to increase the total water capacity of the system which in theory makes it a more stable system.
That said, on occasion I do think about switching it out for a cool acrylic colored one as the plywood certainly doesn't look very cutting edge and has earned me more than one raised eyebrow when I show it to guests!