Functionality is a big word.
The fact of the matter is, it can be nearly impossible to get the truth about whether or not a piece of event technology will work for your needs, and if it'll have the features that you want.
In a previous life, I've been the person on sales calls who was taught to steer the conversation away from talking about specific features in the pursuit of "qualifying the customer better" which is essentially Sales Code for "getting dirt you can pull them up on when it comes time for them to push back."
And it sucks. As a customer, that sucks.
In that scenario a) the seller is usually being condescending and assuming that you've never bought anything in your life and b) you've probably done your research ahead of time, meaning that you just want the person on the other end of the phone to answer the damn question, because you get the gist.
The thing is that we, as purchasers, have a lot to choose from when it comes to our event stack. Not only are there multiple companies that make the same kind of solution, but so too are there multiple different solutions you'll potentially need to consider in order to pull off the event you're envisioning.
Thankfully, we've had over a decade of being able to use the internet effectively to dig up info on previous customers' experiences with the software we're considering. That said, that too can lead to information overload.
Off the back of that, here are two quick resources to help you make faster, more informed choices when it's decision time and you need to commit to an event technology vendor: