I have a layout with mostly Atlas 83 on the main and ME code 70 in yard and spurs. My beef is the spike heads on the Atlas are too large and should be 3 or 4 into each tie plate ( 2 on each side of each rail ). The tie size seems fine though. This is one thing you don't find out 'til it's too late : When making long curves, take 2 or three 3 ft lengths of flex and while they're straight ( tangent ) solder them all into one 6 or 9 footer . You cut off 2-3 ties on the new ends to take on the rail-joiners (fish plates). An Exacto knife slices these real easily.. But be careful that the ties on all 3 sections have their staggered splits on the same side.. I.E. from the underside of each section you will notice the way the ties are all connecting under one rail but under other rail they are not all connecting. This is to enable the ties to spread apart prototypically on the curve. And, the staggered ( ones not all connecting ) go to the outside of the curve so they may widen (fan)out slightly and remain tighter together, tie to tie, on the inside of the curve..