I'll only be able to tell it's compatible with my code. I'll be doing some DMA transfers to timers to control WS2812 LEDS for example. I'll have to think about some more tests to do, but it will never test every possible configuration. Also, thinking about some tests to identify the part. In the end, all it will say whether it's good enough for my purposes. So far, in my opinion, only STM and GD are worth considering. That is based on the presence of documentation and availability of the chip itself.
The parts I've under test are sold as APM32F103 and CS32F103. For this test I don't have any clones labelled as ST parts that I am aware of.
So far I've only seen the GD32VF103 on Longan Nano boards, but I've not yet seen the chip itself for sale. My thought about the chip is it to be a GD32F103 with the ARM core replaced with a RISC-V code, and the peripherals and pinout remain unchanged. So you could replace the chip in an existing design (if it has a full JTAG header available, as no ARM means no SWD).