Chicago Top 3

[Smokey]

Self-described "rock and roll band with horns", Chicago was on most successful rock groups of 70s. They progressed from harder sound to soft rock, and generate memorable hits along the way.

Ranked from most favorite:

1. "Stay the Night": from Chicago 17
2. "If You Leave Me Now": from Chicago X
3. "Just You 'n' Me": From Chicago VI

[Jack in Wilmington]

I really like early Chicago.

1. I'm a Man Chicago Transit Authority
2. Listen Chicago Transit Authority
3. 25 or 6 to 4 Chicago II

[3LB]

love the first 3 or 4 albums

Beginnings
Make Me Smile
Questions 67 & 68

Good call on the I'm A Man cover
honorable mention to their CSN-ish Happy Because I'm Coming Home

[MasterCylinder]

I also appreciate the earlier cuts :

Beginnings -- Questions 67 & 68 -- 25 or 6 to 4


Later, Chicago became very good at the ballad department :

Searchin' So Long -- Hard to Say I'm Sorry -- Hard Habit to Braek

[Smokey]

I'm probably the only one, but liked their later albums better than earlier ones as more jazz infusion is evident in first few albums (not a jazz fan)

But they do have few iconic songs from that peiod which you all mentioned including "25 or 6 to 4", "Beginnings" and "Saturday In the Park".