"So should one not hope to get a sufficiently good quality recording by using the Zoom H2 then? (sorry if this sounds daft, I'm no tekkie)."

You can expect to get very good quality from your H2 Sue, as long as you don't expect to mix several instruments. I use the H2 for voice and acoustic guitar, and it's great. Harmonica breaks using the neck brace are fine too. Beyond that I can patch the file into a digital 8 track and add other instruments/vocals, and add any reverb etc afterwards. Good luck with your H2; it'll serve you well.