Buy and try (within reason)
Woah. Steam just announced it will allow for refunds on “nearly any purchase on Steam” and “for any reason,” from your computer’s inability to run it to you plum not enjoying it. That last one might make developers sad.
There are some caveats, mind. You have to ask for a refund, “within two weeks of purchase and with less than two hours of playtime,” which seems fair enough. After approval, your refund returns to you in a week’s time through whatever method you used to pay.
For specific rules on things like DLC and pre-purchases, check the announcement page.
“Refunds are designed to remove the risk from purchasing titles on Steam—not as a way to get free games. If it appears to us that you are abusing refunds, we may stop offering them to you.”