Being designed by the same person, and having similar hulls, I would expect that American and Nordic Tugs would perform similarly (given similar loading, etc.). I have been out in mine when we had over 25 knots true wind, (wind instrument read 34 knots apparent sustained) but the seas were not bad for that wind speed and we were able to get in and anchored in about 1 hour or so. The wind was mostly on the nose, and the boat performed fantastic. The times we have had to deal with waves on the beam, not so much fun!
However, unless you are put together differently than me, I do have a reasonable mass around the middle section to help with my balance
During Covid, it appears I might be concerned about my ballast, as I think I might have added a couple of pounds!