It makes sense to me to be able to sit where I want (subject to availability of course), avoid the "fast" track and use the First Wing (handy when there are queues heading out the door at busy periods), and escape the crowds in LHR. Added benefits of access to AA Flagship Lounges, plus more redemption availability.

So in summary, I like the more comfortable / convenient travel experience.

I'm aiming to get to GfL in the next ten years so I can keep the benefits in to retirement.