Sorry I didn't get back on this thread earlier. I have the same concern you do Hank. I would much rather they make a yield monitor for my mower instead. That way the passes are always consistent and there is not field loss. Making dry hay, I've heard that field losses can be 5-10%. The idea is really intriguing, but I don't think they quite have everything figured out yet. I have run Harvest Tec products for a while and I must say I'm not overlly impressed with the company. I've spoken with the owner Jeff Roberts a few times and he's a nice guy, but he's a businessman/salesman all the way.  From my experiences on the preservative applicators, it usually takes them 2-3 years to get bugs worked out.