Without knowing the details of your specific audience and business, my initial gut reaction is that you are going to trade off on sales for free samples. If people don’t know your company from Adam, even if they want what you have to offer, given the choice between trying you with zero risk in a free sample vs. paying for the unknown, I would guess 99% of conversions take the less risky path first with the other 1% paralyzed by the two call to actions ;-). Best practice like said above is to stick to one C2A.
That said, free sample may be a great lead gen model for you it is for many other companies. Obviously, your case may be different and best practices are not guaranteed results.
There can be numerous situational caveats to this…
Example, if you are selling leads in an industry starving for them, there is a good chance somebody will risk throwing a small chunk of their budget at you just at the hope of finding a new source of leads.