Symmetry of a pressuregradient microphone (fig.8)

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Hi guys,
this should be the right forum for this special theme - I recently posted some measurement stuff here, but what I will show here is too geeky probably

ok, if you are interested to use a fig8 microphone for M/S recordîng, be sceptical of manufacturer datasheets, because polar diagrams didn't show such details and angle depending frequency responses are normally not shown.

I have done some acoustical measurements in an anechoic chamber with some expensive and well calibrated measuement equipment (not mine ). Here are the results of investigating my Schoeps MK8. My intention was to see how good it is. Unfortunately (I assume but) I didn't know if it is the best fig8 microphone capsule on the market.

The graphs show corresponding angles in one diagram together with the sensitivity-minimum at 90° (for M/S purposes this minimum is the 0° angle of course). The last graph is amazing, have a look what happens in these short steps from 75° to 90° to 105°!



The difference curves:



In my opinion the last difference curve is not relevant. In the most important frequency range the tolerance seems to be according a matched microphone pair and I expect 0.5 dB deviation in my stereo balance using the MK8 for M/S Stereo. Which is really neglectible...

Any opinions to that?
Cheers
Stefan