...It Depends
Like most conversations about the question "Do you like your AMS" - it depends. when I first began using it, I came from a background that included some great collaborators using a very good system. For the first year or two I thought "This thing is TERRIBLE". The structure, the (in)ability to get information out, the complicated processes, etc. As time went on (years), I came to understand that much (or perhaps most) of the problems were with my company - large (for an association), siloed, no consistent process, etc., led to a highly customized system. This meant upgrades were near impossible, and changes were shunned because no one knew what might happen. Also, we started with Aptify rather early and were stuck with an older version.
BUT - from what I've seen, the newer versions are much improved, so as long a new customer stays out-of-the-box, they could have a great product. Aptify as an AMS has matured a bit, although I think the company itself isn't as helpful and proactive about working with customers to improve their use of the product as they could be.