When I worked in Enterprise IT evaluating new products for a Fortune 50 company it was pretty much the same way. The three biggest things that we looked at were functionality, support and the stability of the company.

We needed to know that it could do what we needed it to do and that there were enough support resources that we could get someone on the phone if we had an emergency. It is not cheap to integrate new software into the systems and processes of a large company so we also needed to know that we weren't going to put in that effort and then have the company go under a year later.

Support and stability were the two biggest issues that limited adoption for early stage startups. We didn't care if you had any big name customers. We just needed to know that your product did what we needed and you'd be able to support us for the long term.