Yes, that's more or less what GSam Battery Monitor shows me, around 4-5% battery usage during screen on. At the same time I get around 4% battery drain per 48h due to wakelocks, mostly Play Store Services localisation (GPS always on).
Useful information about the 6T by the way. I almost got that one for the OS and the in-screen fingerprint scanner, but I couldn't get pass the much higher than average SAR value. I expected the Mate 20 to have better battery life than the 6T (even with its LCD screen), but I didn't expect it to be this good.
I actually think Mate 20 is superior OP6T in almost every way except the user interface. I bought a used OP6T since I was dissatisfied with EMUI on Mate 20. However, after using OP6T a couple of days I sold it and went back to Mate 20 for the following reasons.
- As already mentioned, the battery life is clearly better on Mate 20.
- Mate 20 is the prettier phone, smaller bezels and overall nicer looking compared to OP6T.
- Speed is more or less the same but I felt that Mate 20 was slightly faster when opening apps.
- The rear camera is slightly better on Mate 20. Probably due to the large 1.55um pixels on the main rear sensor on Mate 20. I also missed the ultra wide angle sensor on OP6T.
- I like the screen quality better on Mate 20. Blacks are deeper on OP6T due to AMOLED but bright backgrounds look better on Mate 20 and I also felt that the screen on Mate 20 was more crisp and vibrant.
- The screen size is clearly larger on Mate 20 due to 6,53 inch and 18:7 aspect ratio. The screen on OP6T is too narrow and do not feel that much larger than a regular 6 inch 18:9 screen.
The hardware design of Mate 20 with the UI of OP6T would more or less be the perfect smartphone.