OK, good question. I just looked at pictures of the two frames, side by side. No, I don't think the Sun is better except in one way: it has a built in rack. All the triangles formed by frame tubes are nice and small, making for good stiffness. This is on both bikes.

The Sun's price is probably going to be irresistible.

It looks like it has fittings for disk brakes. Clearly, it has bosses for V or cantilever brakes.