I recently purchased some Z Stuff for Trains track and crossing signals to use on my current project layout. I really like these, and have already purchased some additional signals to add to the layout.
You can buy or see what products are available at: https://www.zstuffexpress.com/
I picked up one pair of 3 light track signals and one set of crossing signals, along with a speaker/sound controller for the crossing signals. The installation is easy, with only a pair of power hookups required as the IR sensors to detect train movement past the signal are built into the signal base. You can also attached additional sensors to place down the track to actuate the signals prior to the train's arrival. The track signals can also be daisy chained together, so the signal operations will depend on the signals down the track. So, instead of a red signal changing to yellow after 8 seconds and then to green after another 8 seconds, a signal won't change to green until the following signal changes to yellow, for example.
To install the signals, simply drill a half inch diameter hole about 1.25" away from the track, drop the circuit board that attaches to the signal in the hole, and then attach the wires to a power source. You can attach two other control wires to additional signals, or simply ignore those and just hook the signals up to power, and then they will operate in a basic delay mode, where the signal will turn red when sensing a train, and then 8 seconds after it no longer senses a train the signal will turn to yellow, and then to green another 8 seconds later. In that mode, you can very easily add signals to your layout with little effort.
The signals do have a sensitivity adjustment dial. So, I can place them on a two-track mainline, and trains on the far track won't impact signal operation on the near track if the sensitivity is adjusted correctly. Notice in the image below that the far track signal has turned red, but the near track signal is still green.
The crossing signals work the same way and look nice as well. However, it isn't very realistic to have the signals flash only once the train arrives at the road crossing. So, I've purchased a pair of sensors from Z-Stuff that I can attach to the crossing lights but place farther down the track so they will start flashing a few seconds before the train arrives. You can also connect the two crossing signals together so they both start flashing at the same time.
Overall, these are nice signals, are easy to install, and look pretty good, even in N scale. I plan to buy more of these since having operating signals provides additional interest to a layout.
For much more on these signals and to see how the signals work and operate, check out my YouTube video below.