To be fair there are still options for high-performance cars that don't shaft you on tax - the Golf R for example is only Band D I think (€570) and the M4 is Band F (€1,200). But beyond that if you're the kind of buyer who is looking at something that falls in the top tax band (new M5, GTR, etc. as Big H says) then I don't think the difference of €500 or so between the top rates of pre- and post-2008 tax rules is going to make much difference to you. The likes of the e92 M3 is in a weird category of cars that is otherwise potentially an affordable car for a lot of people, but just gets hit hard by the post-2008 tax rules.

One good thing about the shift in focus from n/a to turbo in recent years is that we're seeing comparable or better performance from cars with significantly reduced running costs.

That said, in general motor tax rates in Ireland are obscene even compared to the UK. When you combine it with insurance and VRT, it makes you realise there are a lot of cars that would be considered "affordable" if you lived in the UK but simply aren't if you live here.