If all of the wear is in the front and that makes the apron 'sag' only on the front that will move the tool down and away from the work. I agree that down doesn't matter all that much, but if the 'away' component is near the same (and it would be if the point of the work and the support point on the bed form a right angle with equal length arms) then the tool will move quite a bit.
In my experience it will only really cause a problem in boring and on small diameter work.
But yeah, $200 was a pretty good deal for a little Colchester.
It'll be interesting to see where they go with the grinder.