The big question to ask yourself is.....are you a multi millionaire?
Some might laugh at this question, but I knew a guy who had an old citation 500. The fuel alone from California to NY and back was ~$20,000. This was after he upgraded the avionics in a $100,000 refit.
A direct operating cost of something like a Mustang is probably along the lines of $1000 per hour (if memory serves right), not taking into account devaluation which will probably be half a mill the minute you fly it out of the dealers.
My buddy used to fly a Falcon for a wealthy chap. His annual operating costs were about £1,000,000 per year (didn't matter to him as he was a billionaire). I don't think that he did massive amounts of flying either, a couple of transatlantics, one to Oz /RTW, the rest around Europe.
If money is not a massive issue, then why not!
If you don't have millions in the bank, then as another poster said, you could always rent. I know of places that would probably rent the likes of a Mustang (after appropriate type rating and hours as PIC for insurance etc...). This would probably cost about $1800-$2000 (?) per hour including fuel. (I can't remember, I think I paid $1100 per hour dry when I rented it).
I'd be inclined to buy a jetprop or something though. That would fall into your budget and the costs are much lower than a jet (though bear in mind a rebuild of a turbine could be in the region of £150,000).
I've often thought what I'd do if I won the lottery...If I won £10,000,000 I'd buy a nice turbo prop. If I won £50,000,000 I'd buy a Phenom 100. If I won £100,000,000 I'd still stick to the Phenom (possibly a bigger one though), but fly BA First Class around the world drinking Gin and Tonic in the back !
