I don't expect other brick companies to be LEGO; in fact I like the diverse designs that JM Bricklayer sells. The Jellyfish offers a very nice looking finished product.
That said...
One of the things LEGO has going for them is that they follow basic building rules. The Jellyfish set designer seemed to throw the rules into the wind. MANY pieces are attached to others by only one stud making for a very finicky build and an unstable finished product. Plates that are meant to appear floating are attached in the air by only three corner studs or wobbly stacked cylinders. Pieces pop off. The collar that holds the stem that holds the jellyfish body becomes unseated when you breathe too closely. And, the large tentacles do not fit tightly and fall off. This set induced more swearing in my home than any other set from any other brick company.
The other issue is that the motor is super loud.
This is my first JM Bricklayer build. After doing this one, I'm not sure there is a second set in my future.