Dang, I want a Spectrum now...
I will say I have had 0 problems with my Picasso II+ it is great cheap board and love the VGA pass-through which works perfect with the A3000s 31Khz output.
You never miss a screen mode with this setup.
But reality is, 1024 x 768 in 8bit 256 color though. But I'm good with that.