FWIW. I own a Citori 625 Sporting. A while ago, a fellow shooter showed up at the Montreal Skket club with a Cinergy Euro Sporting. The two guns were side by side on the gun rack and his gun appeared to have a much shorter LOP than mine. I compared the stock specs on the Browning website, and the two guns are supposed to differ only by 1/2 inch in their respective LOP. Yet, in actual fact, the Cinergy Euro Sporting is much shorter than the 625 Sporting. Cerainly more than the stated 1/2 inch.
Not sure if that trend will also be true for the Cinergy Classic.
One more caveat: The Lightning has a flat rib, whereas the Cinergy Classic Field has a sloping rib. Thus, the Cinergy will have a higher POI, relative to the POA. If you like to see your target and keep it visible just over the bead when shooting, you might prefer the Cinergy over the Lightning. Other Citori models such as the 625 Field have a sloping rib, which I personnally prefer. The 625 Field is slightly more expensive than the Lightning, but it is also a higher grade firearm. You may want to consider that one as well.