This isn't a flame war. It's a review based upon user experience. That's all it is.
Regarding your question about the Ferrari - Yes, you do get to take it for a test drive to make sure that model has the functionality you need. Does it handle like you expect it to? Do the wipers give you, the potential buyer, the kind of visibility in the rain you like? Is there enough leg room for you? etc. Your correct in saying you don't get to keep it, but the potential purchaser has enough opportunity with the vehicle to make sure it meets their basic requirements / expectations.
Same thing with a flat. You get to walk the flat, measure the rooms to make sure your stuff fits, look out the windows to determine if you can live with the view. You're correct in saying you don't get to sleep in it for a month, but the potential renter/buyer does get enough of an opportunity to make sure it will meet their basic requirements / expectations.
Back to the review. Mom and Pop businesses, like I do work for, aren't running IT businesses. Most are barely IT literate. They run salons, restaurants, stores, etc. Pulling up their website to enter a support issue from a phone call doesn't make sense to them. They want some kind of web support system that is easy for them and their web based customers to use. But they want and need to "see" what the front end looks like and how the "look and feel" matches or doesn't match their expectations. They need to watch it operate. with enough limited functionality, to let them determine if its something they can deal with.
I'm not saying you should open up the full functionality in the free version. You put a lot of work into the plug and deserve to be rewarded for it.
The review is simple - because it is currently impossible to see how the front end integrates within a users site, and its currently impossible to watch the front end do a couple of tricks, purchasing it is a gamble. The purchaser may end up spending 50 euro for something that doesn't "fit" their need. That's all.