Whether a credit card is good or not depends on how you intend to use it and for what purposes. I would say that this card would be great for the British expatriate in the US who flies British Airways back to the UK often. It would also suit an executive who travels a lot between the US and Europe with this airline with their company. Having the companion ticket feature means that you can save money when you bring a partner or spouse on one of your trips.
This card is also good for those who like to travel to Europe and spend enough on the card every one or two years to earn enough miles to get a business class ticket to Europe and also to use the free companion tickets. When used wisely, you can really save a lot money traveling to Europe.
But aside from folks who use the companion ticket or travel to Europe, this is also a great card for those who fly short haul American Airlines flights domestically. Why? Couple of reasons. The first reason is because BA miles can be redeemed for AA flights. But more importantly, the Avois redemption is based on flight distance and not simply regions. That means you require less miles if the flight is shorter. This system actually benefits folks who fly short flights versus those who fly long international flights.
In the case of AA, redemption for a US domestic flight starts anywhere from 25,000 onwards. For a ticket that cost less than $250, it simply does not make sense to use your miles. For example, an AA flight from Salt Lake City to LA requires only 9,000 Avios miles. You certainly would not get that redemption rate with American Airlines.
So I've got to conclude this review with the following view. I think BA has one of the best airline cards out there in the market. The reason is that it is not just useful to folks who take a lot of transatlantic flights, but also for those who are savvy enough to use their miles for business class tickets on international flights. But more importantly, for those who travel with AA or Alaska Airlines domestically on short haul flights, you might also want to consider this card because you will find that you need much less Avios miles than either the AAdvantage or Alaska Mileage Plan Miles.