When a reviewer cites a band's "maturity," it frequently means the group has exchanged spontaneity and freshness for calculation and predictability. That's certainly the case with the Peppers, whose latest has generated raves from easily pleased scribes, even though it's basically two discs' worth of been-there-done-that-better-in-the-past. Stadium features loads of material, but bulk is no substitute for creativity. "Dani California" sets the stage for what follows: It's melodically, vocally and lyrically tired, and the most memorable riff John Frusciante offers up is one from "Purple Haze." Not that Frusciante is the biggest problem here. His solos there and on the likes of "Readymade" may qualify as classic-rock pastiches, but at least they give off some heat. The opposite is true of watered-down funk exercises such as "Tell Me Baby" and the drippy "If," during which Anthony Kiedis gets in touch with his inner David Gates. This last number is so feeble, it should be put to bed with a glass of warm milk and a sterilized bedpan. If that's maturity, you can have it.