Level is a funny thing. I didn't think it mattered much when we started camping, but now I can sense it if it's off too far. I leveled the frig, countertop, bathtub, etc. and nothing was in syc, but all were close, so I chose the frig as the bench mark, leveled to that, then once I got it right on with my digital level, went outside and installed the bubbles on the front corner of the trailer. Now when we pull in to a site, I know instantly how many Lynx blocks I'll need side to side, then crank to the bubble after unhitching for front to back.