Hiya Joe and welcome to ECF!
I don't believe prefilled are at all "worse" than blank. Mechanically they're the same. But some folks say they don't like the
e-liquid in the prefilleds. I've had some excellent prefilleds and some that taste like ... LOL...it's all in what you prefer.
There's maybe a slight monetary benefit to using blank cartos. Using only prefilleds could get expensive if you don't have
e-liquid to refill with, but if you're all about convenience over cost, find a prefilled you like and when one is empty, just toss it, get another and go...
Hope this helps. Good luck!