I got the stupid idea in my mind to build an ROV, since I’m still a student my budget is very low. Since the cad files are for download I though to give it a try and just print them. I modified them to fit an Roxxy 2824-34 motor form my old drone that was sitting in the stock for years.
My fist tests are quite promising:
By now I printed the case and then I will build test rig.
Next things to do, I will get a more suitable motor (slower) and replace the bearings with polymer underwater bushings ( Igus H370FI-0203-03).
So don’t get me wrong I think the T200 are quite cheap for what you get, but still a lot of money if you need 6 (or 7) of them. If you just messing around. I think the printed version can’t by fare compete with the real once but. for my intention (sweet water lakes with max 30m depth) I think I they will work. (Besides at some time my budget will increase 
)
Finally here is a picture of my preliminary ROV :
