It wouldn't bother me if its been well looked after and had parts replaced as and when.
Flywheel juddering on pull off and plant the accelerator in 4th to check for clutch slip and excessive vibrations.
Black smoke is signs of a boost leak and blue smoke is signs of the turbo burning oil.
Cam 'should' be alright, with out taking the rocker cover off you cant check them. Just listen out for clicking noises coming from the engine.