I find it effective, especially in building core muscles.
Cheap, and much heavier than most dumbbells, easy to manage.
It looks cheap, but useful for strengthening oblique muscles with water bucket side bends.
Can use it in deadlift too.

Anyone with similar experience?

I doubt you can load the pails to more than maybe 20kg per hand? I don't know. That's like a 40kg dumbbell deadlift. Won't do much aside from making you better at picking up pails of water.

Yes that is correct. So you'll be doing a 20kg per hand. Not very effective as a barbell deadlift substitute imo.