Fast or slow? Fast works better, in this case.
Donovan's Brain carries on the fine tradition of rock 'n' roll bands that take their names from 1950s sci-fi movies (see also Creature With the Atom Brain, This Island Earth, etc), but their musical cues come squarely from the 1960s. Album opener "Take Me With You When You Go" is a satisfyingly peppy little confection made from breathy lyrics, jangly guitars and a rolling bass line that keeps everything moving along. The band is at their best when offering up such nuggets: the piano-inflected "Morning Side Dream" and relentlessly poppy "Restless Nights, Many Dreams" are lightweight, hit-the-gas-and-drive songs that carry the listener along with few demands and many familiar sonic elements.
The band get into trouble when they try to slow things down into spacer/stoner territory; the lethargic "As the Crows Fly" and "Manager of Time" sound like they were recorded when the band was underwater, which is a lot less interesting than it might sound. Listen to Turned Up Later for the good-time uptempo tracks, but be prepared to hit the Skip button a few times.