I have had a 3d printer for a couple of years now and find it enjoyable and useful for certain things. I have made accessories for my wife's knitting hobby, I have made parts for a weaving loom, as well as extra bobbins for spinning wheels.
On those applications, the surface texture didn't matter so the minuscule filament lines weren't a problem.
I tried making some small parts for r/c tug boats, but the after printing clean up and sanding and painting took more time than it would to just fire up the lathe and mill. Again, that was with a filament type printer.
There is a fellow in England that makes jet drives for r/c boats with good success, so tough, durable goods are possible.
The big deal seams to be the cad software. It is tough for some of us older folks to learn it and understand it, but with some perseverance, it can be done. Also, there are a few very good programs that are free for hobbyists.
If you want to print a "kit" that someone else designed, you can go to Thingyverse.com and chose any of the thousands of free files that are ready to go ... just download and print. They also have a large number of "customizable" files that start with a basic design and allow you to make what you want from it. No software purchase required.
The machines for printing with resin, like Shapeways does, are getting down around the $1000.00 mark now, although they are still pretty limited in size of item printed, and the resin is still fairly expensive.
Is 3d printing the ultimate in modeling? No where near. Can it be interesting, and add to whatever hobby you are in? Most definitely. Will it relace my lathe and mill? Nope!
This will be a 1/48 scale water/fuel tank. The printing lines clearly show, but with a bit of filler and paint, it will work. It was part of a steam wagon kit on Thingyverse. I am altering it to suit my needs, and If I display it in public, it comes with it's own label that you print out that lets everyone know who designed it and gives credit to them.