Vodafone had no custom version on the N900 (though i re-flashed from the UK to Global). However on the N97 they did have some rubbish. I plan on getting the N9 sim free and then getting a sim only contract with either vodafone (as i get corp discount) or with 3 - who do unlimited data for £25 a month on a rolling contract (which you said you have). I am not sure if it covers Ireland but if you're interested in joining voda let me know and i'll check.