Panzer III & Stug III succeses against T-34 and KV's?

[Stiltzkin]

I do have seen some intances, esp. during the first 3 months.

Yes, Mcensk is such an example.
This went both ways, Panzer IVs have been occasionally mistakenly identified as Tigers during the war.
This makes the 10% more plausible now, I wonder if the majority of the 3,7 were Paks or short barreled Panzer IIIs.