Not to rain on your parade, but one of the reasons for shooting 8x10 is contact prints. For enlargements, you appear to already be set up for 4x5. I dare say you would not see much difference in enlargements between 4x5 and 8x10 until you got to prints that measured in feet! But hey, whatever floats your boat.
well, either you don't shoot both formats or you haven't made enlargements from 8x10 film. Which is it?
I ALSO, can see the difference in an 11x14 enlargement. I wouldn't own the enlarger for the hell of it.