Smurf is good pretty much anywhere you can use Romex with the flexibility to retrofit different conductors. I have it in my house for those attic runs that I didn't want to be crawling around in insulation to make. You can push/throw it quite a ways in the 3:12 attics we have here where headroom is only a foot or two.
As a totally unrelated aside, this is pretty tough stuff. I know it is not listed for "outside" but I have some on my boat that has survived over a decade and a half in the Florida sun. 3/4" smurf is the perfect size to sleeve a steering cable and the cable inside still looks like it just came out of the box. I also split a short piece and installed it to protect me from "wild hairs" on the boat lift cables. That is still flexible too.
Like the Carlon RNC straps and conduit body covers, the older smurf connectors are NOT U/V protected but the tube itself seems to be.
