My view of this is that if you can afford to spend the money without becoming destitute then I think you should do it. The significant benefits include lounge access (including a guest), priority boarding, earlier seat selection, fast track security etc. These apply across all OW airlines and not just BA.

I have to say that on the few occasions recently where I have flown with Delta and - shudder - Allegiant that I have really missed all of the perks that come with status.

However, be warned: once you start to climb the greasy pole there'll be no stopping you