Hammer H2 and Quarq Dzero - data difference

I am chasing some variability between my trainer and my power meter.
I am getting some high .IF on my outside rides so I started trying to diagnose if the issue is equipment or bad ramp test.

Today I put my outdoor bike with a quarq Dzero on the Hammer H2.
I made sure to do a trainer calibration, I did a calibration last week also.
I also calibrated the dzero, it showed 53 two times.

I did an easy work out and compared the numbers.

Quarq
742kj 197avg/w 202np 62:50min
Hammer
761kj 206avg/w 209np 61:31min

I was trying to get my chromecast to work so I got off the bike and forgot to stop the garmin is the reason for the time difference. These numbers are pretty close, is this something where I should be doing more or is this acceptable?

there will be a difference due to driveline loss ( the H2 would be lower usually but not always) and also figure in the (approx) 2% accuracy if one is high and one low thats 4% sppread of 200 so 8-10 watts there ( rounding numbers ) ,…so you appear within accepted norms,… you will drive yourself crazier than reading the DJ/TR thread backwards trying to get these to match exactly… my 4iiii reads about 10-12 higher than my H3 on average.
seeing this I would lean to a bad ramp test.

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Try a long form test.

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