Like almost everyone the first starts out camping. I did the bubble levels, have had them fall off- get knocked off- and glass broke.. They worked ok I guess.. but got tired of them..My dealer suggested a small level just inside the door.. I took his advice. I had a small 10" level at home and tried that..I have never used anything else..i really don't worry about spot on either.. If I am off an 1/8 to a quarter bubble to the high side on the slide out..i just leave it.. when you slide out it will almost level out.. And I look down the window frames, going front to back level.. I get really close most every time...(but I do check the level inside the door)...
