I just replaced the wheel on our tongue jack, so I'm hoping for smoother rolling now. As noted above, the wheel is handy for hard/smooth surfaces and I wanted it for repositioning our VT on our asphalt parking pad at home. On the road, the wheel rarely comes into play except to slightly adjust the trailer position when hooking up. We also have a two-wheeled trailer dolly that I use to move the trailer at home and this has eased the load a lot. You put it under the hitch point, push down on the handle, and roll it into position (with the trailer jack wheel in the up position).
Our new Bigfoot
only has the jack pad rather than a wheel, so we'll see how that goes. I don't anticipate really being able to manually re-position the 28' Silver Cloud
whether I have a jack wheel or not!