I was reading this since I ran into the same really frustrating issue with the styling (RadFormDecorator won't style RadInput without workarounds).
One way to make the solution "global" may be to add a control adapter - e.g. write a class that extends from ControlAdapter, then register it in a .browser file to extend RadTextBox, RadDatePicker, etc.
This is the approach I am going to try and take to hack my way to getting the radinput controls to look nice so I can integrate them into the rest of the app without making the forms look strange.
I haven't finished testing this approach yet but here's my example:
public class InputAdapter : ControlAdapter
protected override void OnInit(EventArgs e)
Page.PreRenderComplete += new EventHandler(Page_PreRenderComplete);
void Page_PreRenderComplete(object sender, EventArgs e)
if (Control is RadTextBox)
RadTextBox tbInstance = Control as RadTextBox;
tbInstance.EnabledStyle.CssClass = String.Empty;
tbInstance.HoveredStyle.CssClass = String.Empty;
tbInstance.FocusedStyle.CssClass = String.Empty;
tbInstance.InvalidStyle.CssClass = String.Empty;
tbInstance.EnabledStyle.CssClass = "rfdInput rfdRoundedCorners";
tbInstance.HoveredStyle.CssClass = "rfdInput rfdRoundedCorners";
tbInstance.FocusedStyle.CssClass = "rfdInput rfdRoundedCorners";
tbInstance.InvalidStyle.CssClass = "rfdInput rfdRoundedCorners";