Ive had my Mk1 done, got it done at Ultra Window Tint near Maidstone, in Kent. They did a quality job in about 2-3hrs. Cost £180 which was heaper than a few other quotes i had (and included VAT!). I wasnt sure what tints i wanted when i got there and he explained the options, basically light, medium or dark, or a combination. The medium and dark were illegal for the driver and passenger front windows cos they dont let enough light in, but if i wanted them done hed have happily done it for me! What i got in the end was light all round, apart from the rear windscreen which is medium. That darks down the car quite a lot, and means that it pretty dark without being silly (or illegal). I would recomend that you get it done professionally, having seen a few tragedies with the diy (but Paul16v seem to be an exception!). Whatever you get done youll like, its one of my favourite mods. Essay over, hope that helps a bit!
Jon