Works well if you want to 1) Fulfill your own eComm orders. 2) Want the ability to do dropship with 3rd party retailers. 3) Want LOT# control (e.g. if you're in the food industry). There are a plethora of companies that can do ecomm fulfillment but they don't have the ability to do option 2 & 3.
It is very well suited for minimal human interaction while gathering requirements as certain fields are pre-populated while capturing the requirements. There is an easy import feature to add requirements to the system. Training for the users isn't a complicated process. Integration with other collaboration tools needs to be made more easier and robust like that with Sales Force or Slack or Microsoft Teams.
Very hard to find the products you're looking for on the site if you don't already know exactly what you're trying to find. Lots of similar/identical products with uninformative naming conventions.
Poor faceted navigation.
Entire site is painfully slow.
The policy of automatically closing inactive accounts after 12 months, with no ability to re-open it upon customer request, is crazy.
Pricing on most commonplace IT products (outside of things like HPE servers) is not competitive at all, it's almost always cheaper to just buy on Amazon, and even when Ingram is cheaper, the difference is so negligible it's pointless to bother.
Prosoft Solutions is a good tool but just for ease of integration, we do have some teams in our organization using ServiceNow tools as well. Within our team, as we wanted to attain faster training and customer support, we have gone with Prosoft.