[cobirds] Chipping or Brewer's? (Boulder)

Every fall I agonize over juvenile spizella sparrows at the Boulder Community Gardens.  Are the attached photos of a juvenile Chipping Sparrow or Brewer's Sparrow? I'd appreciate any comments!

For the bird with its chest toward the camera, I'm leaning towards Brewer's:

Reasons it could be a Brewer's:

1. No dark loral stripe

2. Complete eye ring

3 "Dopey" face (at least seems that way to me...)

4. Steeper forehead

Reasons it could be a Chipping:

1. Bill seems bigger than the "tiny" Brewer's bill. Does this trump the four Brewer's field marks above?

For the bird with its back toward the camera, I'm leaning toward Chipping:

Reasons it could be a Brewer's:

1. No dark loral stripe. 

Reasons it could be a Chipping:

1. Incomplete eye ring

2. Bill seems largish

3. moustachial stripe seems darker and more distinct

Thanks!

Richard Trinkner

Boulder