I like that it is easy to use with no training required! It has been very helpful in my shop's success as we have seen an increase of customers who are interested in our products but do not know how they can purchase them online or even if there was such thing available locally (we're located outside NYC).
The only downside so far would be some minor issues when adding new categories - sometimes you need help from their support team which isn't always immediate at times. We've noticed more sales since implementing this tool into our store compared to previous years where people were just browsing around looking without any intention of purchasing anything.