IHG would certainly like to see Crowne Plaza as an equal match to Hilton and other full-service (4)5-stars.
But i think it's very much local market specific: some CPs are pretty ropey (off the top of my head, the SFO Burlingame one is a good example), while others (try the ones in Laos, or Indonesia, [Bandung] ) are up there with the best.
There again, Hiltons, too, can be dogs - and overall the Hilton-Hilton position has fallen, although the marketing power of the brand is still associated with quality and luxury that (in many cases) is over-stated or no longer applies. Doubletree to me seems closest to CP; while the ultra-Hiltons (Conrads etc) eclipse most Intercontinentals.
CP is the most uneasy brand in the IHG stable. In the US may of the properties are old, shabby, tired and over-priced; while in Asia they offer a very different proposition.