We loved the Magic Bands BUT we were onsite so I didn't pay additional per band. It was amazing to put the band on (we put them on in the car on the drive down 4 hour drive) and were used to them by the time we arrived. I never took mine off - slept, shower, everything with no problem.
If the people that you are traveling with will leave the bands on and give you peace of mind, then go for it. If they aren't the type to wear a watch, then they might not leave the bands alone and then the convenience of the bands won't do you any good.
The bands did make life much easier, no juggling, no digging for cash - tickets, FP+ and door key on your wrist. Last trip was the first one with the Magic Bands and the first time we took advantage of room charging. I would just stop by the front desk every couple of days and pay the balance with gift cards that I had received.