GarBow Bobalong & Pique thanks for that, some good food for thought. Although I think the idea really is to move down to one car not have a hack and a 2 seater. If I was going to have a roadster and another hack for everyday I'd just keep the MX-5, no questions about it. 9 years along and still worth 1/4 of its OMV which can't be said for many cars. I don't think a classic is a runner, I'm fond of my comforts in the car and as good as they might be, I'm useless mechanically and don't want the hassle of maintaining a classic. The MX5 presently costs about €1,500 a year in tax, insce and fuel (excl dpn/NCT/service) to keep on the road and for the fun it gives is probably worth it, but it only goes out for maybe an hour or so on a weekend now so that really equates to €30 for an hours driving. The 3 costs about €2,000 a year for tax/insce/fuel. I suppose it's the thought of two lots of insurance and road tax for very small mileage is what's getting me thinking.
The 3 series cabrio is probably the nicest looker in 4 seaters and is well in the price range but a grand for road tax, no way. I guess the ideal would be if Mazda did some sort of folding tin top in a 4 door ( like the focus ) as TBH I find the Mazda brand reliability and service from our dealer second to none.
Thanks for the thoughts folks.