The reason these are going on sale now is that a new USB C monitor is coming out soon. The entire Macbook Pro and Macbook Air line will most likely get USB C ports and Skylake chips before the end of the year.
If you have a current generation MBP or MBA, this is a no brainer. They are beautiful monitors that are virtually break proof. I’ve had mine for 4 years without any issues. The convenience of connecting and disconnecting along with an integrated power connector is amazing.
Do I need to purchase a thunderbolt cable to use this with my early 2013 Mac book Pro Retina? Or does the monitor come with a cable?
It comes with a dual headed cable that has a thunderbolt and MagSafe power port for your laptop. Note - if you have a newer mac, you will need a MagSafe to MagSafe2 adapter
Picture of cable at http://www.apple.com/displays/