This entire issue can be summed up by one succinct quotation:
"We don't need air conditioning in the Blackhawks, so we didn't think it would be an issue" in the Lakota, [an U.S. Army spokesmen] said. "But when we got the helicopter into the desert, we realized it was a problem."
This is a classic example of one of the services not having the foresight to accurately predict requirements. This is what happens when a bunch of guys with a single airframe mindset (the '60, in this case) try to apply their past experience as the sole basis of comparison for future mission sets. This same sort of reasoning (by a bunch of USMC '46 guys) is the root cause of many of the V-22's specific limitations.
Both the USA and USMC suffer from the integral problem that since aviation is not their core competency, their respective service models of fielding new aircraft can be somewhat limited in scope. This is not to say that their aviators and aircraft aren't highly capable, just that they are sometimes hobbled by a lack of perspective by their aquisitions folks who are hard pressed to think "outside the box" when publishing RFPs and later on during DT/OT. I've flown with both services and seen this first hand.
Bottom line here...despite my allegiance to the U.S. and the implicit need to "buy American," anyone that claims Eurocopter or their product is lacking is simply trying to cover up the fact that U.S. Army didn't do their homework when envisioning the flight envelope in which the LUH (regardless of who finally won the contract) would be forced to operate.
Just my humble opinion....