Haven't hunted with the AB, but have developed loads with it. If my info is correct it is only made up to 260gr in the .375, so it is not appropriate in my mind for DG just on weight alone.
The Partition, a great bullet, took bullet technology to a new level. Could it be used on buff? Yes I'm sure it has. But just as the Partition was an advancement, the bonded bullets are also an advancement. The A-Frame for all intents and purposes is a bonded Partition. So if I had to choose between the NP and A-Frame or North Fork, it's the AF or NF without hesitation.
Nosler has listed in their catalog a 300 grain Accubond as well as the 260. I don't know how "new" this product is.....but I agree with you that the 260 grain might be a bit light. As for the partitions, I use them in my .30-06....the 180 and 200 grain versions shoot 1/4" groups at 100 yards from a rest; I find it hard to pass on that type of accuracy, even if better bullet technology is available!
Interestingly enough, partitions didn't shoot very well in my .338 Win mag, but accubonds did.....and accubonds didn't shoot worth a tinker's damn in my .30-06, but the partitions do......go figure!
I plan on testing whatever I can get my hands on, but I just waited 4 months to get some more accubonds for the .338, so while I may find a "favorite", I certainly don't want to limit my options in case I can't find what I need prior to going to Africa on my next trip, whenever that might be.........I have been waiting for 3 years for a new run of .35 Remington brass and .22 rimfire is still next to impossible to find at reasonable prices around here.
One's gotta takes what one can gets, if you know what I mean..............