i can't speak for any of their recent products (NJ/CK3) that are bus based controllers, but I have worked with a few analog controlled CS1-MC421 systems that had a complete G-code library. This was 15+ years ago.
There were the usual platform dependant quirks in implementation and no toolpath optimization, block look ahead, etc., that can be found in a modern motion control. Think Fanuc 16i and you'll be in the ballpark of capabilities.
The newer controllers claim to have all of these features and more, how well they actually work, I leave to others to weigh in on as I am primarily doing motion in A-B these days.
From what I have been able to glean from conversations with their sales reps you have to be cautious when selecting downstream Ethercat hardware unless you are going to implement a full Omron package, as with every other manufacturer they don't always play well with others.