The Three Questions
How Do They Work On Trails?
These conversions work ok on trails but do not give you an easy comfortable ride because you have less stablility on turns but the still can turn just as good on a trail as any other sled. Because of the three rail design on the front ski you get more tracktion when turning. The ski angles to the ground when leaning so you never lose tracktion on the when leaning on turns. So if you want it for trails then be ready to kick your foot out to keep stable.
How do they work in powder?
Depending one the type of conversion you will either get great handeling or poor handeling. If you get a long track conversion you will have great handeling and with a short track it will be good handeling.The type of track to avoid is the trail tracks because they are smaller shorter with shorter lugs.
Are The Conversions Bad For The Bike And Do The Bikes Have Enough Power?
The bikes that are recommended for these conversions is 250cc race bikes all the way to 500cc+ but no matter what size of bike it will wear out faster then when used in dirt because of the weight and size of the thing the motor must turn. These high power race bikes have plenty of power for the conversion so you don't need to worry about that, but you do need to do maintainence constently to make sure that your chain is tight and everything is normal.