Got my BA Gold card but it's just sitting in my wallet looking pretty, never having been used even once. I've only flown BA twice many years ago, before I knew anything about FlyerTalk or even FFP's, and I don't plan to fly them in the future, unless perhaps I get a customer located in the UK.
Since the demise of Diamond Club, I've just been crediting my flights to OZ's Asiana Club and am now a lifetime *G with them (reaching the 500K status miles mark gets you lifetime Diamond Plus). I went from splitting up my miles between BD, OZ, and TG to strictly OZ now, although my flying was greatly reduced at the same time, so I'm happy with just one FFP, especially being I'm now lifetime after being cheated out of BD lifetime by BA's takeover of BD and not recognizing their responsibility to keep the promise BD made.
Being there's little chance of me ever flying whatever the remnants of BMI are, nor joining whatever FFP they may ever introduce, BD/Diamond Club is just a memory to me. Still have over a million miles though that got transferred to Avios. Not sure how I'm going to use them. Perhaps book some trips for my friends if they're flying on routes where they can be spent. I tried to book a vacation together with a friend using the miles, but availability was so terrible, and having to do multiple transfers and purchasing tickets on some routes meant the cost would have been as much as just buying a direct ticket, and we would have wasted a couple of days of the vacation just waiting around for a transfer flight. If worse comes to worse, I might have to just use them for hotel stays, even though it would mean terrible value for the miles.