Both.
Amiga works but the I/O limitation of the PI + current TDM of the signals between the Pi and the Amiga means ChipRAM performance isn't as high as it should be. Interrupt behaviour is not quite the same. This leads to some incompatibilities. Not everything just now and again.
Emu68 the alternative JIT 680x0 engine for PiStorm is very good amazing performance. The design exposes the Pi Hardware to 680x0 and you write drivers in 680x0 for AmigaOS. The drivers for the Pi SD card controller and RTG driver for the Pi GPU are very impressive. I am Patreon of this work. But development has stalled. The 680x0 SANA-II WiFi driver for the Pi WiFi is taking a very long time. The 680x0 Picasso96 GPU driver uses no hardware acceleration. The Poseidon USB stack driver for the Pi USB host controller I don't think has even been started just discussed. Nothing is stopping any other developer writing the drivers. The documentation is available. But so far only Emu68 author has attempted anything. He's only one person working part time.
ST (and CDTV) compatibility is not possible yet because bus arbitration, bus error, and processor state pins are not driven. They are wired to the CPLD but it has no code to drive them correctly.
The lead PiStorm developer Claude is very much a free spirit and does what he wants when he's interested and at the moment PiSTorm isn't interesting enough. The remaining 10% of the challenge is much harder with far less reward than the 90% he's graciously done and released free for anyone to pick up and run with
Don't get me wrong there has been contributions from other people but development as a whole has stalled. You can see it from the activity in the dev section of the PiSTorm Discord server compared to "the old days"