So after touting the pros of my A23 wheelset for so long on the interwebs (not really that long - 18mths or so) I was washing the bike in lieu of my impending race tomorrow and find no less than 5 cracks in the rear A23 rim. Luckily I got a set of Kinlin rimmed wheels built up around Christmas and so have a fallback set. There was a noise very similar to a loose spoke noise I had on my old wheelset of my previous bike, so just put it in the go see the LBS soon basket. That stated about 2 weeks ago. 2 of the cracks are small and just starting, and the other 3 are substantial. The way they have grown seems to be straight out from the spoke nipple and then along the rim where the material would go thinner for the rim wall.
Anyway, so I'm hoping to just replace the rims and nipples and keeps the hubs/spokes to keep costs lower. So unless someone can point me at other rims, it looks like the DTs, Mavics and A23s are my replacement choices. The A23 has ERD of 601mm and the Mavics have 602 and DTs 599 so all should match to my existing setup. I'm hesitant to go back for an A23 due to the failure mode and the whispers of their quality being a bit ho hum of late. I would lean towards the DT440s as I liked the transition to the wider A23 rims from my previous CXP30 rims although they're "only" 21mm wide. Wheels will be my everyday set although I'm a little lazy and will race on them more often than as well. They will be mating to 32h Ultegra hubs and my weight is sitting at around 115kg/250lb.
Worst case is I go for new spokes and broaden the search substantially.