Engine and transmission works like a charm, even though both are still original parts from 1988.
It accelerates slowly (0-100 Km/h @ 12sec, including the turn to the freeway), but has no problem keeping up with the rest of the traffic.
My Sunny has some mild case of overheating in the summer - to it's defence, it's been around 25-30 degrees Celsius here the last few weeks - but once driving on a freeway, or just somewhere over 60 km/h it gets enough air to keep it cool without the radiator fan that occasionally kicks in if you have to drive/stop frequently.
I don't know have many others had the same problem.
The car has been very reliable for the short time I've owned it, the engine runs smoothly and emission values are way under the set limits.
It is also very comfortable and roomy in the cabin, shame you can't say that about the trunk; Don't get me wrong, you can fit many 6-packs of beer and a sub-woofer there if you wish, but might be tough to fit in hockey sticks or something else long or moderately high objects (e.g. lawnmower).
It's really hard to find anything bad to say about this car.
Yes, it has it's small quirks and problems, but for a car that is nearly 18 years old that is to be expected.