In theory, the reason why you put a aero wheel in front (if you only have 1) is that the front wheel sees more wind than the rear. The rear wheel is mostly obscured by the seat-tube (If you have one). Disc wheels are not suitable for the front because in x-winds steering can get sketchy, and this is why they have 3/4/5 spoke aero wheels.

That is how it applies to road/ tri riding. But since Aerospokes are neither aero nor light, I don't think it really matters.