Yeah the SAM wasn't the prettiest, but I liked it. It wasn't exactly Spectrum based either, as it featured a faster CPU but happened to have legacy compatability with 48k speccys. Apparently there was a feature where you could edit the screen colours of speccy games when running them on a SAM, but seeing as I've never used one I can't confirm it.
The Archimedes was a lovely machine... 4096 colours, with 256 on screen at once, 8 channel sound... How come the hardware sucked? I saw a couple of Arch demos and was very impressed.
I too remember Silica selling those Mega PCs back in the day too... You can get an Amstrad emailer machine today that's Spectrum compatible too.