Ok ... firstly..... All mini's are minipits
.... whether its R53/R56 they both have their issues.
The drive on the turbo is nice, but I personally feel its less involving than on the supercharged model. They feel very different to drive, Both handle very well, with the R53 feeling more solid, go kart like and connected to the road. And the R56 feeling more modern and less of a wrestle.
It's personal choice really. For me, the R53 ticks my sensory boxes. Steering as if your holding the wheels in your hands, Eager engine with plenty of punch down low in the rev range. And then you have the noise...You simply cannot beat the wail of the SC on the power and the crackle crackle pop bang when lift your foot/come down the gears.
Fuel economy is better on the turbo model with the charged model guzzling gas by the gallon...Seriously, economy is macca ( my bmw 330 was better on fuel
problems wise... dont know about the r56 turbo model... but R53.... look out for the usual stuff clutch, brakes stops starts, smoke from the exhaust etc. Engines can weep oil from rocker cover and crank pos sensor. Cam chain tensioners seem to need replacing a lot and make sure the cam chain itself has been changed if the engine is pushing 80-100k. Front suspension strut mounts can split and or have mushrooming( google this term to see what i mean ) ... if it has a sunroof, check it hasnt been leaking into the passenger footwell. Otherwise they are pretty solid if been taken care of.
Thats about it.
Google, schmoogle, test drive, enjoy, purchase and Grin, grin and grin again.