Somewhat depends on the size of the plane as smaller planes may do better with a lighter weight covering than Ultracote or Monokote (the 2 most prevalent coverings). However, for most planes, most people use Ultracote as it gives a good finish and is relatively easy to work with. Personally, I think Monokote stills gives a superior finish but is harder to work with and some folks have had problems with some rolls of Monokote not sticking properly or the adhesive being grainy. I recently finished re-covering a 33% Extra, purchased new rolls of Monokote, and did not have any problems so your mileage may vary.