Given the single-hungry, compilation-friendly, attention-span-impaired climate of popular music, it's not surprising that mix-tape-style compilations from notable DJs are bigger and more popular than ever. And no DJ is bigger than Funkmaster Flex, who presides over popular radio shows in L.A. and New York when not making regular appearances on MTV, releasing albums, and holding it down at the New York hot spot The Tunnel. The third installment in his 60 Minutes Of Funk series was subtitled The Final Chapter, so it shouldn't come as much of a surprise that Volume IV feels halfhearted at best. Almost entirely eschewing the seamless mixture of old and new material and the exclusive freestyles of previous albums, Volume IV consists largely of new studio tracks from some of the biggest names in hip-hop. It's got star-power to spare, with Eminem, Nelly, DMX, Ja Rule, Lil' Bow Wow, and countless others turning in appearances, but it feels as much like a series of favors being repaid and mutually beneficial relationships being formed as it does an actual mix tape. The presence of Notorious B.I.G. (apparently even the dead have to pay homage to hip-hop's most powerful DJ), M.O.P., Eminem, and DMX keeps the festivities lively early on, but halfway through, the album devolves from uneven to dire, with uninspired turns from Da Franchise, Lady Luck, Shyne, and Ja Rule doing little but filling space. Even more damaging is the album's fatal lack of cohesion: Wildly different tracks simply follow each other, with little logic and even less flow. There's too much good material on Volume IV for it to be written off altogether. But in its mercenary devotion to whatever's popular, it has more in common with instantly disposable current-hit collections like Now That's What I Call Music! than with essential mix-tape-style compilations like Soundbombing II and Sway & King Tech's This Or That.