Let me try again: You're looking for a piece of software, you need it, and are ready to buy. Let's call it a CRM and the feature you're looking for the ability to add a new contact from the main screen. (It could be anything and any feature, but just as an example)
During the demo, you love the software, the people instill confidence, and you can see yourself using this everyday. If it takes three extra button clicks to add a new contact (giving you a workaround) would this make you happy?
Or you're really happy with everything, and the choice is to sign the contract and we would have the button before install date (written in the contract.) Would that be a better option?
I'm interested in how you as the person listening to the demo, would take those two options (giving only one option would be presented during the demo) Does this make more sense?
As a reference, The guys at Close.io use the first option ( http://blog.close.io/) patio11 (who is kicking around here) uses the second option (http://www.kalzumeus.com/)