Magic Bands and MM+ would be terrible at DL. FP+...wouldn't really have a problem with it. Really liked the flexibility at WDW.I enjoy having Magic Band atWDW and it could work at DL. I think with new technology coming out all the time the bands are probably already obsolete so it would make sense not to use them at other parks.
I don't think it's "wouldn't work well" as much as "wouldn't work well enough to justify the cost." It could work just fine, but there's really no need for it. Hotels and dining are a tiny fraction of the Disneyland model compared to WDW.DCL is the next best place for it to go...but that said, I don't see why it wouldn't work well at Disneyland, outside of the fact they prefer their multiple ID and picture ticket system they have now (unless you are AP)...
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