I finally got the OK from the doctor to go diving and was able to test 8.00 in the water.
It certainly looks like the correct temperature data are being recorded to the dive log unlike prior to 8.00.
Here's a comparison of the logged data from my last dive with 6.00. The temperature readings are from my Citizen Hyper Aqualand, Shearwater Perdix AI and Garmin Descent Mk1 (6.00):
Here's the data from Saturday's dive with the Mk1 on 8.00:
I consider the Citizen to be the most accurate and the Mk1 is very close to that now, considering it only records to the nearest degree.