For flashlight use the relevant measurement for battery resistance is the DC IR. As mentioned this meter measures something different which might or might not be useful.
All these measurements seem very close. Some batteries listed I would have thought to have higher resistance. So these are very accurate numbers? Shows perception does not mean much. 
This is a multimeter test method of battery internal resistance, but the battery's internal resistance is very small, the error is relatively large
There is also a great resistance between the conductor and the conductor, and it is easy to change
HKJ has an comment of this instrument
This YR1030 instrument measures the same cell and test many times ，almostly the same data
Some chager have function of tested the internal resistance , but the error is large, each test data is not the same, each slot data is not the same
A123 26650 have a lower resistance, please check
I just got a YR1030 to go through some older cells to decide if they should go into the recycling bin. Also, I’m interested to see how well old and new cells match each other. After collecting some info about how resistance changes with time, I might sell it on. At least that’s how I justified spending $50. I used a battery holder for the cells and clamp for the switches and tested at room temperature. Here are a few newer cells that weren’t already listed.
Molicel 21700 P42A 3.54v (they come discharged from Liion Wholesale) (9.31 mΩ) I like how these have a slight button top allowing 2s in some 26650 lights.
Molicel 21700 P42A (9.57 mΩ)
Molicel 18650 P26A 4.19v (11.44 mΩ)
Samsung 30T 3.57v (6.97 mΩ) slightly higher than Trisky’s cells from 2017. I never tried to calibrate my meter. They did match each other well though
” ” (7.08 mΩ)
Shockli 18350 1150mAh 4.16v (23.0 mΩ)
Shockli 18350 1150mAh 4.15v (24.3 mΩ)
Older but barely used
Efest 18350 700mAh 3.99v (32.4 mΩ)
Efest 18350 700mAh 4.02v (37.1 mΩ)
Liion Wholesales protected cells. Re-wrapped PANASONIC/SANYO NCR18650GA 3500MAH 10A 18650
3.66v (37.4 mΩ) compared to Trisky’s unprotectected GA cells, with a measurement of (24.5 mΩ). Not sure if this is a well designed protection circuit or not.
Switches from Mountain Electronics
Tested a few Bare Omten 1288 with the clamp right next to the plastic i.e. would increase to over 4 when tested on the thinner part of the tabs closer to the ends.
3.24-3.61 mΩ
Reverse Clicky Switch 250V 1.5A (4.95 mΩ)
Omten 1217 Reverse Clicky Switch 250V 1.5A (3.10 and 3.58 mΩ)
Inkidu, 1KHz AC resistance or impedance figures can be accurate and useful for ideal resistors like switches, but not so for batteries in this league of ours.
For comparison purposes, cold DC internal resistance for a Shockli 18350 1150mAh is close to 60mΩ (discharge curve inferred value, check its review at lygte-info.dk).
This is not to discourage anyone doing what he/she thinks it is good though. Thanks for providing information. 
Still working my way through some old batteries.
(4) unportected Evva 5200mAh 26650 (vappower) (38.6-40.9 mΩ)
(4) Efest 26650 (red) (19.7-21.0mΩ)
This A123 15 Ah pouch has been in storage for years. Not something you handle with a watch on. Got a few more to test. I’ll be curious how they have held up through the years of storage.
I get 4.0 mΩ for both of my Samsung 40T's @4.16v with the SM8124A AC tester.