I'm a bit confused and hopefully can get some accurate information. At the RTW OW site I am able to construct a DONE4 that takes me to the payment page with a total price of 97,800 ZAR (first seg JNB-MAD). I wanted to book via the AA RTW desk but they kept faring the base at about 15% more with the total at 111,000 ZAR. I had them reprice it and it came back the same. The explanation I got was that they have to use either the AA/BA/IB fare and the OW site was using the QR fare but couldn't explain why the fare difference. She also said "AA RTW desk is the OW desk for all RTW tickets and we can do all changes you need in the future regardless of the carrier".

I will need to make date changes in the future and maybe routing and wanted it to be easy and thus prefer AA but not at a premium of 15%. If I book it via the RTW OW site do I need to deal exclusively with QR for changes and seat selections if issued on their stock?

Thanks