I don't know Czech, but Italian is extremely consistent in the way it's written, so it's at the top of the list with about one or two orders of magnitude less data.
Czech pronunciation is actually very close to Italian (and both close to Latin). We don't do the "ce" and "ci" and "gn" things (we do a "di, ti, ni" thing instead), and we use diacritics to soften certain sounds (ž,š,č,ď,ň), but even ignoring all that and plowing right through, an Italian speaker pronouncing Czech text should be easily intelligible and even spot on for some words.