Agreed, first is best, concerts I've been to are almost all sold out of merch after the show
If your looking for shorter lines go during the show after the first few songs have played. Otherwise show up early. The good thing there is if its anything like when I've been there a lot of places on every level to buy stuff. Enjoy
Or go why other bands are playing. Have a great time.
I think that it would be better to go before the concert starts. The lines may be too long after the concert is over.
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