You'd have a K over a T?

I've owned both and even I'd take the T.
I think both engines have their flaws. The K suffers from HGF, the T suffers from an oil leak at the front right hand corner of the block, again HG related.
The T's have a high pressure oil way at the front right hand corner of the block. The old style gasket used to wear away when the head expanded and contracted, eventually failing causing the oil leak. If you were unlucky you'd lose about a litre every 1000 miles or so.
The triple layer Klinger gasket (fitted to all T-series after 1996) is re-inforced and stops the oil leaks.
The 620Ti is a fantastic car. Not really in terms of chuckability, but the performance for the money you pay is astounding. I've seen them go for as little as £300, and to get 200bhp for that amount of money is fantastic.
As davidstone said, they're basically a Honda Accord so expect them to be screwed together pretty well.
Oh, ShakenNstirred, there was nothing wrong with the K. For its time, that engine was WAY ahead of the competition. It was, and still is (in my eyes) a damn good engine.