Jon:
Sorry, forgot to address your question about repairing the screen. All I can tell you is what I know from my own experience, and that is with the SP III. After about two years of use, I had a bunch of small scratches on the screen. So, I thought I could get rid of these by taking a bit of the plastic polish that we use on aircraft windows, and polishing the screen. WRONG move. What happened was that I polished the anti-reflective coating right off the screen, and what remained was the plastic screen cover only. It had a surface on it like a mirror, after I finished polishing it, and the GPSR was just useless for daytime use (other than as a vanity mirror) after that.
I wound up sending the GPSR back to Garmin's service facility in the UK, and they installed a new front cover on it for me. If I recall correctly, this cost me about USD $40 in the summer of 2002, and that included shipping to and from Switzerland. Garmin turned the unit around pretty quickly - I was only without it for about a week.
Anyway - if you can live with the scratches, live with them, because the only alternative seems to be replacing the front cover of the GPSR.
PanEuropean