There isn't much about this in English online. There might be a lot in Chinese but I don't speak nor can I penetrate the great firewall of China. Thus, I thought I'd start a thread because I bought a Seafrogs SF-01 (Also known a Meikon SF-01 or SF01 or SF 01) recently and I have just gotten the proper batteries for it too. (18650 10A 3500mah protected with button top, about 70mm long - Vapcell P1835A) It is quite particular about battery size - it needs at least 68mm long 18650 batteries with protection board and a particular type of button top that is rather pointy. The Vapcell that I mentioned is exactly what works. I can verify that much. At least 68mm, 69mm preferred (from the manual), and the 70mm that the Vapcell I have seems to be fine too.
I saw threads and a video before where folks were unable to get the old Seafrogs ST-100-PRO to do anything except fire at one particular power and had some issues with it... I can say quite confidently - the SF-01 has fixed that particular issue while manually testing! It can indeed shoot at 7 different power levels at the least. I have not received my sync cord in the mail yet - so I cannot do any kind of fancy testing at the moment but when I do receive it - I will do such. It is also just a manual strobe - there is no TTL functionality as far as I can tell (there is no mention of TTL and there is no TTL knob on the strobe itself).
Here's a gallery where I took a picture of a greycard that's included with my colorchecker passport. This is a distance of 1 meter from the flash to the subject (±0.5"), F/22 aperture, ISO 100 (Sony A9), exposure length of 2.5" to let me manually trigger the flash in test mode. I did not use the diffuser - bare strobe only as to get maximum output. Maybe I should've just taken a picture of the colorchecker itself to give you an idea of CRI or color correctness from the flash itself. https://imgur.com/a/rf4i4op
If someone asks - I'll do that and they can analyze and share the results. (As I don't really have a good way to do it myself - I don't have any special software to determine that I think)
Flash recycle time at full power with the "ultra fast" recycle mode is still about 2-3s. It isn't under 2s most of the time for full power shots. Personally, I'm not too bothered at the moment.
The actual important part like - will it blow up when I submerge it and will it work with a 5-pin sync cord - I will also be testing. Just wanted to test the flashing part first. Thus, the first post here. Interested in what people want to test/see out of a strobe besides it lasting a single dive.