Trust but verify!
You'd be surprised at how far out of level a rig can be and the refer is still fine with the newer units. If you're comfortable walking around in the rig it's probably close enough. I noticed ours was low in front today and put a level on it. It's a half a bubble off, just like the owner my wife would say.
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft
Charter Lifetime GS Member, SKP, FMCA,
RV'ing since 1957, NRA Benefactor Life, towing '14 CR-V