epic and Josh, I think he's probably looking for a Colorado tire for his Superfly. Right, Finn? So our Vermont / Maine experiences may only be partially applicable.
Having said that, I basically have the same take on the Schwalbes as the other guys. I had a set of Nobby Nics that were very light for volume, and were awesome in every condition except wet-over-hard (e.g,, wet rock), where they were truly, scarily atrocious. Here in New England, that's kind of like saying a ski is awesome in every condition except manmade hardpack - i.e., a non-starter if you don't have a quiver. For you, however, they might be great. Anyway, I sold them after a half dozen rides. Never tried the Racing Ralphs. Several local riders have them, but it's an expensive experiment. Probably the most popular 29er all-rounder tire here is the Rampage. Affordable and decent, according to all reports. I have not tried one. Hard to believe it rolls all that well, considering how slow the Nevegals sometimes feel, and how similar the two treads appear to be.
Totally agree with Josh that the DHR is too much tire for your Superfly. What kind of rims does it have? Assuming it's got normal skinny XC rims, right? If so, I really don't think you want to go with a big tire like a 2.4, even on the front. Plus it's an XC bike. Doesn't really make sense to me to be running huge tires on something that svelte, that's designed to blow past people on the climbs, etc. You're just blunting the bike's strengths, without really buying much in the way of burliness or cush, since nothing else about the frame really supports that.
Personally I keep coming back to the Ardent 2.25. It's not the best wearing tire. (The side knobs tend to wear out on their inside faces. At least for me.) It's not the best in wet conditions, as Josh says (but not horrendous, either, IMHO). But it does roll very nicely, it corners well, and it's reasonably light. It's very predictable. I really like that tire. Currently I'm running one in the rear, with a Specialized Eskar 2.3 on the front because the side knobs are beefier for better cornering in soft conditions, and the compound is slightly better in the wet than the Ardent's. But it's not perfect either - definitely feels slower, and really needs an all-mountain rim. (I made a mistake going with the Arches on my RIP 9; should have gone with the Flows for that bike, or just gotten more of an XC machine like a JET. Next MTB will definitely be the new Turner 29er XC bike. Had a Burner for years and that thing was such a great frame.) In a dry climate I would probably ditch it for something lighter, with a less open tread pattern.
epic, I had a Conti mountain king with the Black Chili compound on the front of my 26er for a season, I have never seen a tire that cleared mud as well as that thing. However, I'm never really happy with the Conti tread patterns for my local conditions. They never seem so to have really solid shoulder knobs. Maybe that has changed in the last couple of years; I haven't really looked lately.
Josh's point about leaning the bike is very well taken. If' you've got good conditions, you're not going to be riding on eggshells like we sometimes do here, when it's all wet roots everywhere. You're going to want to commit at speed, and you need a tire that rewards that.