Most of the horror stories you hear about the RX7 are due to people buying high milers, cars which haven\'t been looked after or not looking after them themselves.
If you do the right research, buy a car with either low mileage or a rebuilt engine (BY A REPUTABLE BUILDER) and look after the car well, running costs won\'t be any more than another high performance vehicle. Fuel consumption is always going to be on the high side, the rotary engine has always been thirsty and strap two turbos onto it and fuel economy will suffer even more. Insurance is not as bad as one might think if you go to an RX friendly insurer (check out the \'Insuring Your Rotary\' section).
As far as the modified cars thing goes, yes there are quite a few cars out there which have been modded to some extent or other, and again if it is done properly and not too extreme this shouldn\'t have much effect on the reliability of the car. Things to watch for though, most mods will improve airflow, but without increases in fueling this can have a detrimental effect on the longevity of the engine. For a reliable, fun, allround driver the best bet would be a low mileage, standard car sourced from one of the reputable sites (Rotary Imports, Newera, Jimmy\'s, etc also RX Motors have a few for good prices)
Hope that helps :wiggle