Speed stole the thunder from its own CD. The seminal Speed girls, now in their 20s and reunited for the long term, sing mature reinterpretations of their teenage anthems of friendship and growing up in Speedland~The Premium Best Re Tracks~. But since we’ve already heard them perform those songs as adults—mostly live, but sometimes in studio recordings—in the 2001 and 2003 Speed reunions, this self-cover album isn’t surprising.

That said, Speedland is still a damn fun album. No matter how many times these songs are repackaged, they’re still a joy to listen to because they’re strong pop music. Speed has qualities rare in modern J-pop girl groups: distinctive songs with a funky groove penned by Ichiji Hiromasa, unique and skilled singing, and chemistry from the members’ genuine friendship (the four met and formed at the Okinawan Actors School). So yes, we can forgive the girls for recording a third studio version of “White Love” because it still sounds good.

The changes to the songs range from a new coat of polish (“Nettaiya”) to remodeling (a breezy house remix of “Wake Me Up!”). A new bridge gives Speed’s 1999 breakup single “Long Way Home” a more hopeful mood than the bittersweet original. “Snow Kiss” and “White Love” stray less, but their arrangements have a modern freshness and cleanness. “Breakin’ out to the morning” has a pulsating rhythm and incorporates the ending rap Speed performed in live versions of the song.

Others don’t work as well. The keyboard-based “Steady” lacks the depth of the brassy 1996 version, and “Nettaiya” doesn’t reveal anything new.

Lead singers Shimabukuro Hiroko and Imai Eriko show off how much their vocals have improved. They now sing the ad-libs on “Body & Soul,” previously left to backing gospel singers. Their adult voices bring smoothness and maturity to “Precious Time,” a nice contrast to the original’s shout-singing. Imai sings in a slick and controlled croon, and Shimabukuro incorporates technique from her favorite genre, jazz. They sometimes strain to reach notes they first sang more than a decade ago, (see “Alive” and “Go! Go! Heaven”), but it’s inevitable.

Even though the new vocals are technically better, they don’t match the appeal of Speed’s teenage singing. Although their high-pitched sing-shouting was an acquired taste, it had an infectious exuberance that could only have been recorded by young girls who were truly that excited by the future.

“Gonna keep on growing up!” Speed proclaims in “Wake Me Up!” In the 1997 original, that sounded like a positive attitude toward life’s trials. But listening to the girls sing it in 2009 reminds the listener of how much they have grown up. Since Speed originally broke up in 2000, Imai has married and divorced and become a mother, Uehara Takako has stripped for an artsy photobook, and all four girls have seen their solo careers dwindle or disappear. And despite all these adult experiences, Speed isn’t keeping their promise of growing up. By reuniting and reperforming its old songs, the group is reaching back to its childhood glory.

It remains unclear what direction Speed will take next. The act has released two singles since reuniting last year—Ashita no Sora, a mid-tempo tune in Speed’s classic brass sound, and S.P.D, an R&B song that was written by overseas musicians and sounds like Justin Timberlake’s “Sexy Back.” However, only the former appears on Speedland, and the latter sold worse than the usual Speed CD. In a TV interview, the girls said they couldn’t see Speed still together five years from now. In that short time period, it would be unsurprising if they struck to what pleases rather than striving for evolution. As this album—somewhat sadly—demonstrates, nostalgia suits Speed. If you don’t worry about the group’s evolution, the recycled music is pure pop pleasure.