Magicbands are the best invention since sliced bread! The ease of not dealing with those ridiculous cards is out-of-this-world great! I cannot say enough good things! We used them for room key, park entrance, dining plan, charging everything we bought, EMH and FP+.
Fastpass+ worked quite well for us, too. Lines were short, so we didn't have to use them very often. But, when we did, they worked great. I loved that I could change them on the fly with my smartphone... I did that several times.
My only gripe was that we couldn't park-hop with them. On multiple days, we did AK in the morning for safari and EE. EP in the afternoon to eat and drink around the world. DHS at dusk for RNR and TOT. Then MK for wishes and over to EP for Illuminations.
On those days, I booked FP+ for RNR and TOT (and a throwaway one). But, I would have loved to use the throwaway for a safari in the morning instead of standing in line.
When they finally allow park-hopping, FP+ will be perfect. IMO
I should also note that I went into this with a lot of trepidation and angst because of all the naysayers on here. But, they worked great for us. We do have friends who traveled nearly the same days as us... she has a few complaints... but, she was so anti-MB before we left that I couldn't even talk to her about them. She contacted me several times before the trip complaining about them and saying that she didn't want them.
I think going in with a positive attitude and knowing there are minor limitations with the FP+ system will help you appreciate them more.
I'm hoping to write a trip report. But, if anyone has any questions, please ask here.