I seriously wonder if any decisions are taken as a result of downloading trial software.
I would be curious to know. I can see people trying say, quicken at home for 30 days, before deciding to buy.
But, I cant imagine an enterprise trying a piece of software for 30 days and deciding to buy or not buy. I am sure some do, but I dont think thats the way to go about it.
In my mind, trial software is good for trying it out. But as soon as you move to the next step of getting even a little bit more serious with it. You would want to talk to the vendor, get a full blown copy and work with them to make sure the install is done in a way that the vendor supports, as well as one that meets your needs. If either of them cant be done, then that software isnt for you, however good it might appear to me based on the trial download.
Additional comment (My $0.02 worth):
I would agree with most of your comments.
If you are investigating a new piece of software where you have no previous experience, then downloading one or more free '30' day trial versions may help define your software boundries. I suspect that you don't get much support with the '30' day trials.
Often, it is more effective to purchase a license for a full blown version of the software along with the 'training' and 'support' offered by the vendor (providing the firm is willing to pay the cost).
Recently, I had to recommend a software function to management where I did not totally understand the product. I downloaded 6 or 7 - '30' day trial versions, made a short-list of the final 3, then purchased a copy of the final 2 contestants and then made a final decision.
I have also used '30' day trails which were extended for 6 months until a final decision was made.
There are many ways to use the '30' day feature to help make a good choice.