It's a joke. I'm paying over 600 quid to tax an MX5 here in Dublin- over three times what I'm paying to tax the Evo in the UK.
The country is full of **** cars, and a V8 over here is but a mythical beast spotted as commonly as a unicorn or the common-spotted Hydra.
If you have cars in both the UK and Ireland then (genuine question) what is stopping you simply using the UK car in Ireland?