When mine arrived, you could easily see where they molded both top and bottom from an original hood and carefully blocked off all the factory holes for the weatherstripping clips etc. That made it super easy for me to drill the holes out again in order to transfer the front weatherstrip from my original hood over to this one and have it sit perfect.
Yes, they do. But I haven't had my car out in the hot sun yet to see how it will react. I've had the original low tension springs installed for a few months now and I see no change in how the hood is sitting. Again, It hasn't got any heat from the engine or direct sunlight yet.