I recently finished a 1940-distilled W.L. Weller Bottled In Bond (100 proof U.S.) bourbon, and have open currently Old Overholt 100-proof rye from the early-'60s; 1952-distilled Old Heaven Hill 86 proof bourbon; 1941-distilled Old Grand-Dad BIB (100 proof); 1959-distilled Old Crow bourbon; and possess unopened bottles of 1957-distilled Old Grand-Dad BIB (100 proof) and 1956-distilled Very Old Fitzgerald BIB (100 proof). All of the open bottles have been very drinkable (some are/were fabulous!), and the unopened ones appear to be pristine, with no clouding or sediment.
Cloudiness in an unchilled state in any of these whiskeys likely would indicate some sort of outside contamination, which probably would render them unpotable.