Welcome!
I built a pair of NX Studios a while back and couldn't be happier. I utilized the flatpacks for the cabinets which went together fantastic. The whole process took much longer than anticipated as I work full time and do the speaker building in my garage, so the weather played an important factor. And I'm meticulous, probably to a fault.
Good luck with your build, whichever you choose. Please keep us posted - we love following along with a new speaker build.
Oh, if you make a few more posts, you can then use the search function here and find other build threads, even for your models you're considering.