I've handled the earlier Gen 1 that is part of the Passaround forum. It was an excellent knife, in all respects. This was purchased by the Forum when the price was still under $400, and it was worth every penny, and then-some. I prefered tip-up carry, and would rather have had the flipper option, and I would actually rather have a thinner blade, as well. We had the ?Spanto? blade shape, and it was awesome, as far as looks go, and utility. It was just a tad thick for me. I've recently become addicted to Kershaw's flipper models, and I would definitely opt for that on an XM-18.
After I handled it, I went to Rick's site, and was very dissappointed to see that he wasn't taking additional orders at that time. I need to look again...
Daniel