Also - I just checked my cc bill for another rental I had with Sixt last month in DUB. They overcharged me by 100 Euro despite them assuring me that my reserved rate would be honoured. I now have to go through the whole song and dance of getting MC to investigate.

National in Dublin have done similar things to this to me before also.

It's things like this that lead me to believe that the Irish car rental agencies often operates in a less than honest manner. The only agency that I have dealt with there that seem to be above board is Hertz, but they tend to be very expensive.