For such a little known brand, with seemingly pretty much no dealers, I know a few people that ride Argon 18’s. They seem to universally love them (but I’ve yet to meet a person who has spent more than £1k on a road bike and doesn’t tell everyone else it’s the best thing since sliced bread), so read into that what you will.
From my point of view, they seem very well made, if a little over-engineered (does the head tube need to be that complicated?). I’m sure it will be a nice bike, my money would either go on something with similar performance for a lot cheaper, or something quinessentially Italian (NOT Pinarello!).