The Challengers’ 2nd last album of the 1960s was released in January 1967 was a two-record set and features a whopping 25 tracks. ​

​

'Stranger on the Shore,' 'Strangers in the Night,' 'Somewhere My Love,' 'Work Song,' and 'Cast Your Fate To the Wind' all hail from the Meet Billy Strange album. 'Man From U.N.C.LE.' comes from the Man From U.N.C.L.E. Lp. 'Telstar,' 'Out of Limits' and 'Rebel Rouser' come from K-39. 'Memphis,' 'Lonely Bull,' and 'Wipe Out' are lifted from the 1966 Wipe Out -Pipeline album.' 'Mr. Moto' is the 1965 Surf's Up! version. Go Sidewalk Surfing's lone contribution is 'Raunchy.' The remaining ten tracks; 'More,' 'Taste of Honey,' 'Only the Young,' 'Walk Don't Run,' 'Born Free (who sings the vocal solo on this??), 'Penetration,' 'Theme From A Summer Place,' 'The "In" Crowd,' 'Alley Cat,' and 'Tequila' are all fresh recordings (and would've been almost enough to complete an album). Though most are only available here, a select few of these rarer tracks can be heard on the 1996 compilation album Killer Surf.

​

Curiously, the version of 'Penetration' here is different from their shelved 1963 Hot Rod Album. In fact, there are no pre-1964 recordings included (only recordings). Also, there are strings on 'Walk Don't Run', which I believe is the first time such a section was employed by the band.

​

25 Greatest Instrumental Hits is very much a mixed bag. The uninspired front cover and 'best of' vibe lead me to believe drummer Richard Delvy was beginning to wind down the band's output. The Challengers would release two more albums, Light My Fire with Classical Gas and Vanilla Funk, in 1968 and 1970, respectively. Of the new tracks here, 'Penetration,' 'Tequila,' and 'Walk Don't Run' are the standouts.