Just a note to those installing tortoise turnout motors that I first installed all 27 motors with Option 3 using the AC transformer creating the half wave rectified DC, boy was I wrong! In my situation I lowered my suspended ceiling lower than most (per an MR suggestion) to force your eye down to the layout but in doing so and having installed 4 tube flourescent lights in the ceiling (troughers just like in the office buildings). After I turned on the lights and the tortoise rectified power to the turnouts , all I could hear is loud humming from both. The turnouts all worked but the sound on the locos had to be turned up to max to hear them. SO it didn't take long to change the tortoises to option #2 Bi-polar with too DC tranformers and all is quiet once again! The frequency produced between the lights and the recitfied tortoises must be such that they feed off each other producing the LOUD humming.
So if using flourescent lights option #3 is not reccomended.