@ocelot60- I frequently make truffle butter with truffle oil, and I prefer it this way. I think that the oil makes the butter much creamier than using chopped pieces of truffles. I also like that you don't have to spend as much money on the oil as you would on actual truffles.
If you decide to make truffle butter using truffle oil, you can ensure that your mixture is creamy by allowing the butter to soften at room temperature first. Once it is somewhat soft, stir it with a spoon until it develops a creamy consistency. Finally, add the truffle oil and continue to stir the butter.
I think you will enjoy the texture and the flavor of truffle butter made this way, and that you will love using your it with a variety of dishes.