Seeing that training etc. is much more memory intensive, and wanting to get faster results, I bought an RTX 3090, which has 24G of VRAM. However it maxes out at about 1024x512, only twice as many pixels. Observing the card with GPUZ, it never actually allocates more than 13.9G.
Using the lstein branch, I can't get above 896x512. Similarly, GPUZ shows allocated VRAM never reaches 14G. The interface isn't as good as the webui on hlky either - never mind the web interface, a bigger problem is it doesn't save all the parameters alongside generated images.
This is all running using Miniconda on Windows. On Linux it may be a different story, but my gaming PC is not dual-boot (yet).