Dawg,
Here's a radical thought (not). Since you will be spending a fair pile of money for this track, buy one section of each and compare them. (I'd forget about the ME weathered unless you're into S&M). (I have a mixed batch and plan to use the stiffer ME for straight sections and the more flexible Atlas for curves) If you compare the cross section of the rail (looking at the end), you will find they are VERY similar. You can paint the ties if you are unhappy with the color.
A little historical footnote: The late Ed Duddy (House of Duddy) had ME produce the original flex. If you look on the bottom of the ties, you will see his name stamped there.
Not sure if that is still done since Ed passed.
Simon
PS: I was able to buy most of my stuff new on the secondary market.
