Max,

The number of layerrs of subclassing does not have any noticable effect on performance. The single most influential thing that affects performance is the code you put in the events of the classes.

I once saw Calvin Hsia run a test of layers of subclassing wihtout any user code in any events. He took it to a layering of 1,000 subclass levels without any measurable difference in instantiation time. Of course the key point here is that there was NO CODE in any of the methods that had to run.