Well, there's a third option--Microdrives. There was (and may still
be) a guy on eBay selling 4GB Seagate Microdrives NOS for less than
$5 shipped.
When I first read that, I thoguh you were talking about an endless loop
tape drive that Sinclar used on the Spectrum and QL machines.. I wouldn't
recomend those for anything...
-tony