All of these seem to be based on the ST7735R.
They have very similar wiring. See this ref: http://webshed.org/wiki/18tftbreakout
The screens are all about the same size (might actually be the same)
Header arrangement on the arduino version seems to be much better for hooking onto arduino easier.
The adafruit one and the arduino one are actually probably lead free. The eBay one not so much.
The arduino version and the adafruit version have a PWM dimable backlight...I don't think the others do this.
All three have a micro ad slot.
Will the new arduino TFT library work with the adafruit and the eBay device?
What advantage does the arduino libs have over the adafruit ones? Is it just that they are more processing like?
(I ask all of this because I once had a project that used the liquid ware touchscreens. Communicating with them was always an issue for me. These screens are worlds cheaper and seem very straightforward to communicate with.)