I would rate OW alliance C-.

This is one case where the sum is lesser than the parts

I don't think that I would rate any of the 11 members below C+ (and each would probably lose "1/2 a grade" due to OW deficiencies). Overall OW seems more like a bunch of stores that share a parking lot than an alliance in which all members are working together.

The good

• Lounge access across the board on international trips (some of the Lounges are great)
• Award availability
• RTW and circle products
• Good quality airlines

The bad

• AA/BA: Can't redeem/earn miles on other airline US to/from UK
• Partial credit (25%/30%) on some fares when "home" airline provides full credit on same fare
• No ability to upgrade across OW partners (other than BA & QF)
• OneWorld lack of coverage (for me mainly within Europe)

The ugly

• No elite bonus when flying on some OW airlines (regardless of fare paid)
• Limited code share (e.g. AA has no code share to TLV, I think that BA, IB, RJ & MA) fly to TLV.
• Only 11 members and it seem like little integration (e.g. can't book a seat from one member web site on another airline's flight)
• Other than lounge access, as a OW Sapphire (I have been Emerald for less than a month), I haven't noticed any benefits on other OW airlines
• Can't book OW (involve more than 1 airline) awards online