Anyone using ET5301 electronic load ?

[jusanother]

Looking for anyone with experiance of using the East Tester ET5301 electronic load. It's similar to the usual suspects East Tester ET5410, Korad KEL-103, DingChen DCL6104, etc.
Has a few variants:

ET5300 400W 150V 40A
ET5301 400W 150V 60A
ET5303 400W 500V 30A
ET5304 2x200W 150V 2x30A

Looks to have a useful rear panel, RS232, USB, and possibly remote voltage sense but hard to tell from the AliExpress listings.

Also if anyone could confirm what the signals on the terminal block are, they are labelled S1+ S1- R1 P1 F1 N1 G. Also has a BNC labelled OUT1.

EDIT this looks like the manual even though it says ET13 series, and it does indeed have remote sense.

https://www.easttester-cn.com/uploads/ET13-Programmable-Bentop-DC-Electronic-Load-User-Manual.pdf

[jusanother]

Manual.