Here's my take:

Marriott clearly imposes higher standards on JW Marriott properties that on regular Marriotts in all areas. Some JWs (especially some of the resorts) have been upgraded from regular Marriotts, but most are new-builds.

Renaissance has been in search of an identity ever since Marriott International acquired Renaissance Hotels (many of which were previously Stouffer hotels) in 1997. The brand lacked the standardization of Marriott Hotels. The brand grew under Marriott ownership -- often in locations where there was already a Marriott Hotel nearby -- with conversions and new-builds. For years, it simply seemed to be Marriott's "other" full-service brand. These days, with hotel renovations, Marriott International is trying to position Renaissance as a "lifestyle" brand, somewhat more upscale than than regular Marriott hotels, with more emphasis on style and individuality. Whether a partictular Renaissance hotel is more like a Westin, W, Le Méridien, or Sheraton depends on the particular property.

Autograph Collection proves that high standards don't have to mean standardization. The hotels have their own distinct names, identities, and histories. But the quality standards are high. The hotels range from tiny boutique hotels to mega-resorts. The styles range from historical to cutting edge hip.

Marriott, the "signature" brand, is known for standardization. The hotels are usually good and dependable, but their standardization can make them boring. Recently renovated properties are becoming more stylish. Marriott brand standards seem require more frequent and thorough renovations than Hilton or Sheraton. Some Marriotts are outstanding. Others not so much.