My ensemble has been playing these for a dozen years. "Intermediate" is brilliantly arranged, but (mostly) easy. There ARE a few challenges here, but most are easy to sight-read if you have to substitute in another player at the last minute. The only strikes (VERY minor ones) against this collection are 1) some musicians might not feel challenged by this music, 2) the page numbering is sort of weird--a combination of numbers and letters--in the publisher's attempt to keep the numbering the same for every instrument across all the pieces. For example, the long Handel "Messiah" piece (#35) that ends this volume spans 3 pages in Violin1, 35a, 35b, and 35c. (Tho I haven't seen it, I suspect that the piano part would run from 35a thru 35g or h or i.)

if you don't care about the weird numbering, buy this book. Your ensemble will love playing it. And if it's not challenging enough, buy the sequel, Music For Four--Traditional. (Warning, tho: some of the "Traditional" arrangements may be a bit modern for some of all-y'all traditionalist musicians and ensembles.)