I extracted this iniformation from auntyyochana blog plus my experience.
Dairy whipping cream contains 35% fat and they are more delicious in terms of taste. E.g. President, Elle vire, Even, Frischli. In US, there a number of brands available for dairy whipping cream.
Non-dairy whipping cream is for mousse also but they are not so tasty. It is also suitable for decorating cakes. e.g. of non dairy whip cream: Pour & whip, Topping Pride, Rich, Baker's Mix, Pastry Pridge
From my experience,
I knew that I have to use non dairy whipping cream for cake decoration but I could not find any of those in LA. So, I used the dairy heavy whipping cream and the dairy heavy whipping cream could not hold the shape well as it did not give desire texture for decoration. Then, when I attended the Wilton Cake Decoration class I and I asked instructor whether to find non dairy whipping cream and she told me that I can only get them, Pastry Pride and another one (I forgot the name), at Smart and Final in LA, CA. Recently, I found out that Costco also sell 8lb sized non-premier version Pastry Pride.
The Pastry Pride is available in premier and non-premier version. The premier version does not contain milk, more sweetness and gives more stability. So far, I found only at 8lb size for premier version. The non-premier version is available either 4lb or 8lb. The non-premier version contains milk and less sweetness and gives less stability. But it is a lot better than dairy whip cream for decoration. I usually keep new or left over non-dairy whip cream in freezer.
We can add sugar to whipping cream if we likes more sweetness. The amount of whipping cream used depends on the decoration design. For decoration, I added 1/2 teaspoon of Wilton Meringue Powder to 1 cup of whipping cream to stabilize/ stiff further. The frosting is still great without meringue powder for decoration.
During the decoration, don't place a lot of frosting in the decoration bag as time go by, the frosting in the bag will start to melt. Place frosting a little bit at a time into the decoration bag and temporarily keep all left over frosting in the fridge. The whipped cream frosting is very sensitive to temperature compared to other type of frosting.
For cake frosting, I prefer to use whipped cream frosting without meringue powder as it is easier to spread the frosting on the cake. If the frosting is too stiff, difficult to spread the frosting on the cake.
When whisking, we have to monitor the stiffness of frosting. Sometimes, the frosting is over stiff due to over whisking. Don't worry, just add one teaspoon or tablespoon of whipping cream at a time and whisk by spatula or mixer till get the desire consistency. We can freeze the remaining whipped cream in the air tight container.
To make whipped cream,
Defrost the non-dairy whipping cream in the fridge one day in advance. Place mixing bowl and whisk in the fridge for 15 to 30 minutes in advance to make them very cold. After that, in mixing bowl, add non-dairy whipping cream, sugar (optional), meringue powder (optional) and whisk with highest speed avaible in the mixer. Don't go anywhere, stay beside and monitor the stiffness of frosting until get the desire consistency. Now, we can use the frosting for decoration.