I should warn you that Sonic Mania Plus is only Sonic Mania. I dealt with this months ago after ordering it and returning it and ordering it again. I don't know why they list it as Plus but they always send Sonic Mania. The biggest issue with this is that individual stores have a different catalogue listing of their games than online so lucking out and finding a copy in-store would be the only way to get it at that price.
It was extremely frustrating because they use the same SKU # for Sonic Mania/Sonic Mania Plus and Sonic Mania isn't even listed on their website. They still never corrected it.