Well, I've put in some 70 miles with this recipe having changed to a Vanilla flavored whey powder. Still a little sweet, but it doesn't have the Splenda after-taste (some other sweetener). I make up 1/2 lb in 40 oz H2O (about 1000 kcal, good for ~14-16 miles/4 hours). I'm still waiting for the unflavored whey and unsweetened flavors to arrive.
So the energy has been really awesome. Sips every 5 min or so. After the hikes (8-26 miles) I down an additional 400 kcals' worth as recovery. I think that is helping a lot to boost the glycogen reserve capacity.
One thing I've found is on extended uphills I have a very short explosive energy available to practically fly up about twenty steps without changing heartrate or feeling hamstring burn. What a difference that makes! Those pesky stairs used to really slow down the pace, but I'm easily doing 400 ft elev of 700 ft/mi grade without falling below 3.5 mph, and that near the end of the hikes with 20+ lb pack.
Now a lot of that is physical conditioning, but what a diff the malto makes.
Two changes I'll make: Less lecithin (accumulates on the walls of the bottle) and add 16 endurolyte capsules per pound (2 per hour so I don't have to keep up with those while I hike).