I just returned from 4 days at Bandon, my third trip this year, a personal best having been there at least once a year every year since 1999, despite living in DC!!! I played 2 rounds on Old Mac, 2 on BD, 2 on PD, and 1 on BT.
I think that it will take me many, many rounds to really understand how to play Old Mac, given the scale and complexity of the options, whereas I think I know the other courses very well given how much I have played them. That said, I did learn that the preferred approach on 11 on BT is to the front left when the slope carried my 6 iron into about 1.5 feet
Birdied 7, 11, and 16 that day...
I play to about an 7 handicap and know how to play with the wind and roll. While I recognize that par doesn't matter per se, I found that a couple of tee boxes on Old Mac were really impossible for me, and for the other players that I was playing with. In particular, 11 was unreachable in 2. I smashed a driver and a 3 wood and still had 80 yards in. Similarly, on 16, which I played poorly, my playing partners, one of whom was significantly longer than me, could not reach the green in 2. On 7, I also really had to hammer a drive and a 3 wood to get home one day. I suspect that they are still learning how to adjust the tee boxes for the holes and wind out there, which absolutely howls compared to the other courses. They really need to give golfers a fighting chance at getting home in 2. In addition, we also experienced variations in the pace and break of our putts, given that the greens are still growing in.
I also did not find OM to be as enjoyable as PD or BT. I really like it, but it feels like more work and less fun. I think this will change as I understand how to play it better. For the record, I did shoot 81 and 83 there, and had the privilege of playing 17-18 one day with Chris Smith when he set the course record with a birdie birdie finish of 66 (or 65?)
From my personal preference, I would rank the courses PD, BT (asterisked because I cannot stand 14 or 18, terrible holes), OM, and BD. If I had 7 rounds to play next week, I would do 4 PD, and 1 on each of the others....