I am aware that this is blasphemy around these parts, but I bought (2) pairs of LDC long pants based on the reputation they have, and I was underwhelmed. I mean, they're fine, and I've certainly had worse, but for me they only reach optimal performance in sub-80f temperatures. Above that and they're hotter than pretty much any other base layer I have. The Klim 1.0 long pants I bought OTOH work great from blast furnace temps all the way to 50f or so, and as far as I can tell give nothing away to the LDC stuff in any way. Also the Klim fly is much better, and the Klim stuff is better at gliding around under my over-pants, be they Kevlar jeans or other over-pants. I will admit that 2.5 days is as far as I've gone in one go in these pants, so I can't speak to the 5 day thing.
On a side note, as it happens these Klim 1.0 jobbers are on closeout at Revzilla right now for $25 a pair. They run a bit tight (and ya I'm well versed in wearing stretchy underlayers...they're really a bit tight/size I promise) so maybe go up one size.