:thumbsdown: Not only is that one not a compilation, FP, but it doesn't even have 'Rose of Cimarron' on it.
GS - The ultimate collection has RoC, Heart of the night, and Indian Summer on it.
http://tinyurl.com/ccyjnft
Those three songs (plus 'Keep on tryin'')
are on The Essential collection 1975-1982.
http://tinyurl.com/cf98aru
Which is not to be confused with the similarly-titled album 'Essential Poco'.
http://tinyurl.com/ctu99xm
You might find it helpful to read the review (probably the first one shown) by Arthur D. O'Brien for this album.