>>4432503I bought an R8 and found it to be wholly underwhelming. Returned that shit rather fast.
Notable issues included build quality, overheating, and a shutter that sounded like a wet rag being tossed around a washing machine.
I haven't tried an RP, but I don't think it has the overheating issues. It also has a limited DR compared to other FF cameras, and some funky software limitations that were "solved" by the R8, so in some ways it's a downgrade but that's reflected in the fact they still sell it and for 60% the cost of an R8.
Now, that being said, some anons here have an RP and they love it. It's a cheap way to get into full-frame cameras and as long as you keep a couple spare batteries around you should be solid.
If the choice was between APS-C and an RP, I'd say get the RP any day of the week. You can get a used RP for $800-900 AUD on ebay and I spent that much on my R50; I'd go back and get the RP if I knew better at the time.