Plastic Bags bend when watering causing spillage, also bags and plastic pots don't breathe like fabric bags.
I like fabric bags, they are reusable and easy to clean out.
Fabric bags allow the roots to breathe and I believe reduces chances of mold and bud rot. JMO.
I usually leave several inches of pot/bag at the top so when I water, with plastic if the water hits the side of the bag it bends n allows the water to spill, maybe I am a dummy and it's my fault but with fabric I dont have that issue, with fabric though sometimes the water will seep through the fabric causing spill.
The primary reason I like fabric is cause it breathes, better for roots.
I have the handles on mine so moving and rotating them is super easy, even with the 20 gallon ones.
Also, if you have high humidity issues plastic bags will collect moisture instead of absorbing it like fabric bags, every little bit helps.
Personally, I like my plastic pots. I tried the plastic grow bags and didn't really like them. Transplanting was a PITA when I used the plastic bags. With the pots you don't really need to worry about spillage, as long as you don't go crazy and dump a gallon of water in to it at one time lol.
Really though, it's all about personal preference. Try a few pots and a few grow bags and see which one you like best.