Yes, that dataset is derived from the 2009c asymmetric T1 template except that the SSW version has several volumes inside it for skull, no skull and masks, and it has been "unifized" to remove bias across the brain and keep intensities around 1000 for white matter. The MNI152_2009_template.nii.gz is only the T1 volume. The MNI152_T1_2009c+tlrc is a third version that has been scaled to 255 and stored as byte integers and has not been unifized.