What is the major difference between RNS-E and F unit?

what do you mean 30% more (more of what?) :lol:

Hardware-wise there is not to many differences. You can load latest software to any of available units and you will have desired functionality.

Since E & F units are pretty expensive & rare (unless you buy it from dealer for top$) still the best choice is EU unit with US software.

Thank you! I actually meant 30% more on price.
But really thanks for your comments.