If you change the model away from 'B' to 'Master' you do get the ability to load SSD/DSD images. Not sure why that is Master-only.
However, my biggest concern with the 'official' BBC Micro core is that it still has the bug where the last vertical line isn't rendered. You can clearly see this if you boot Acornsoft's 'Starship Command' - the upper screen area is bounded by a box, but the rightmost vertical isn't drawn.
There's an 'unofficial' core here: https://github.com/sharpie7/BeebFpga_Mi ... 220320.rbf
This has SSD support and fixes the graphics glitch, but I seem to recall there were other issues with it. Sorry, been a while and I can't remember the details.
Feels like the BBC Micro core could use some love. It's my favourite 8-bit of the era.