Do whatever you want, although I'm not sure you really need DM status. F lounge is great, but I mean most of us are in there on a weekly basis so hence the convenience. It's just a place to get work done quietly, take a shower and eat some food. You can get a guaranteed seat on J, which is also great, and 24 hours advance notice for Y. I use these all the time for business but wouldn't fathom doing it personally just because the cost would get prohibitive...full fare J tix can get expensive if you're paying yourself, and even full fare Y is pretty expensive. Finally, even as DM I rarely see op-up because of the routes I fly (CX730/840) and often do F anyway (or maybe I'm just terribly unlucky) and I think you do that same route too. You don't get any special bonus miles or other things...but I suppose there definitely is a price for DM. It's the price you're paying for all your tix to do mileage runs, and I guess if that cost equals the benefits - both real and perceived - then go for it.