I have taken a look at the recalibrated C01 frames for LLO and LHO.  See LLO alog  21961 , for the LLO version of this.

I grabbed the H1:GDS-CALIB_STRAIN (online) and H1:DCS-CALIB_STRAIN_C01 (recalibrated) data from the Caltech cluster, and generated the ratio of the spectrum at time which we expect both the C01 and C00 to be correct.

The data is stored in the calibration svn at:
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Runs/O1/H1/Results/C01

It was generated by the script:
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Runs/O1/H1/Scripts/CHECKS/compare_C00_C01.m

Below I attach a ratio of the strain between C01 and C00, from GPS 1128249017 (Oct 7, 2015 10:30 UTC).  This is a time period when the front end models and GDS pipeline matched our best knowledge of the instrument and were used to generate the recalibrated C01 data.
 
This should be compared to LHO alog  22291 , first attachment.  Similarly to LLO (see LLO alog  21357 ), we believe the small 2% differences at low frequency are due to minor mismatches in the front end filter realization against our full calibration model which the GDS filters match well against.

The large narrow frequency 5% differences are around the DARM calibration line (at 37.3 Hz) is similar to LLO (see  21961 ).  The other higher discrepancy is I believe related to the front end filtering handling of certain notches, which Kiwamu had to reduced the Q for in the calibration.  See LHO alog  21332  and  22738 .