Question regarding "Unlimited Storage"

I have a question regarding the box "business plan."

I understand that box only allows 5GB per file on the business plan, and that's entirely fine. However, I am working as a system administrator for a small photography business with about 150-200 TB of images, with each image being about 10-40 MB. I was wondering if box will still uphold this promise of "unlimited storage". Or if we will have to end up paying extra for using so much storage. 

I have seen other posts regarding the file size limit, but none about the actual limit of "unlimited storage."