Standard two roller thirdrail pick-up works well 99.9% of the time. There is always that one unit where the rollers would match the two holes, (dead power spots) that back to back switches create.
Weaver E8 can find the holes. The Atlas 6924 relay boards can solve the problem with a lot of work.
Some say Model railroading is a series of problems to be solved, that's the enjoyment. 
When Atlas did (4) roller pick-ups, many of the problems went away. SW-9 model.
