Yep, I seem to remember reading the 2D was an exclusive run for Midway, but perhaps they were not selling etc. as Midway blew them out a long time ago, pretty cheap I think the 3-15's were $600 or so. I've seen the 5-25 as cheap as $700. Once that started others showed up at a couple other dealers on clearance as well.
Posts #43/44 cover the differences between the two versions with diagrams. Given the choice at the same price I'd take the 7C everytime, the fact that the 2D does not illuminate the tree or any numbers in the reticle alone is a plus for the 7C version that illuminates the whole reticle, I also prefer the open circle dot compared to the cross in the center.
That said I consider the 5-25 Gen 2 one of the best value choices, so if value is the main plus, I'm not sure paying $200-300 more for a reticle option still follows that path. It's all a $ game though, you can say $250 more for a 7C isn't a big deal, but then it's only another $250 to a Nightforce SHV, and another $250 to a 3-18 razor gen 2, another $250 to a razor gen 2 4.5-27, and another $250 to the new NX8.