3rd party sellers will not provide you the support you will likely need. 90% of 3rd party sellers for proprietary products such as Nomad and shapeoko are actually scammers. Go with the original, and save yourself the hassle and worry.
One thing that is a perfect indicator: Nomad comes with a meshcam license. A 3rd party seller will probably sell the license too, but days or weeks later, you will get a “invalid license” message because they have resold your license key.
I’ve had nothing but bad experiences with 3rd party sellers, that’s why I just buy from the manufacturer. Some lessons are best learned the hard way, however. So do what you feel is right, and cross your fingers!