The new Element definitely bucks the trend as far as pedaling characteristics, looking at most of the RM bikes at the time of and before the new Element, there's a lot more "WTF?" going on, with extremely low anti-squat, even at sag point, meaning it's just going to mush up hills. The harder you pedal or fight back, the more it'll mush. On these older RMs, it's far worse than most horst-link implementations. I believe that's what the poster above is referring to.
That said, the new Element seems to keep a fairly steady % above 90 throughout most of the travel. That's pretty impressive. The Pivot 429 is still a bit more, but it may not be a drastic difference in feel, especially because it picks up a few extra % points in smaller rear gears (like where you'd stand and sprint). The only area I'd be a bit skeptical about is the rear suspension leverage ratio, which appears to be significantly progressive, going from about 3:1 down to about 2.1:1. While progressive initially sounds good, this would be a good curve for a coil shock, not so much an air shock. I think the net effect with this much progressiveness coupled with how air-shocks are inherently progressive is it would end up pretty harsh on the bumps.
Anyway, I do like my 429SL a lot (just back from a ride tonight). I like how it handles, I like how it puts the power down, the suspension does a good job, etc. It's a good racer bike and also good for places with smaller mountains, like the midwest, south, etc. I got it to be a racer-bike, as I have a couple other bikes for other purposes. I think they did a good job of balancing out the characteristics on it. I think if you have to put a 120mm fork on it, 34mm or bigger stanchioned fork, 2.3 tires, and so on, you should really consider the 429 Trail, over the 429SL. Both are great bikes, at least I know the 429SL is!
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