Mavic Cosmics perform quite well as complete wheels in spite of their square spokes, I'd expect Pillar's round cornered rectangles to be somewhere between those and the proper elliptical CX-Rays. Up against CX-Rays and Aerolites, though, the PSR-1432 has about 50% more cross section area for only 10% more frontal area, so you could build an equally stiff wheel with fewer Pillar spokes, which might offset the worse Cd. Right down among the nitty-gritty of marginal gains, the choice between 18 CX-Rays and 12 PSR-1432s might come down to correctly guessing the distribution of yaw angles you're going to encounter.
Mavic Cosmics perform quite well as complete wheels in spite of their square spokes, I'd expect Pillar's round cornered rectangles to be somewhere between those and the proper elliptical CX-Rays. Up against CX-Rays and Aerolites, though, the PSR-1432 has about 50% more cross section area for only 10% more frontal area, so you could build an equally stiff wheel with fewer Pillar spokes, which might offset the worse Cd. Right down among the nitty-gritty of marginal gains, the choice between 18 CX-Rays and 12 PSR-1432s might come down to correctly guessing the distribution of yaw angles you're going to encounter.