I've built up a set of Velocity Deep-V's and they are excellent wheels. They are round both laterally and radially. So I would expect Aeroheads to be the same. Also from what I have heard, Velocity makes excellent rims.

If you want a really stiff rim, check out the Deep-V's. But you have to consider the extra weight the deeper section adds. My set are built 32 spoke 3x on high flange Phil Wood track hubs and there is no way I can flex those rims in a sprint.