When flying JFK/EWR to London, I find it so much easier and cheaper to upgrade from WT+ to NCW as compared to AA. I also like BA's NCW product compared to AA's J product.

The down side for me is that I would never get lifetime status with BA and that in order for me to earn any kind of elite status, I have to buy premium fares on BA and its OW partners. However, I've already achieved Million Miler status with DL. Hopefully, that would be sufficient when my traveling slows down.