Other than weight, is there any real difference between frames made of 4130 and frames made from 853?

The thicker the tube the stiffer it will be. Lower grade alloys are drawn thicker thus the tubes will be stiffer.

What Nessism said if the tube diameters are equal. But if you're comparing the older, slightly thinner-diameter 4130 steel tubes (usually bikes made before the mid-90s) the 853 in its larger-diameter form should be similarly stiff, with a ride that's either slightly livelier or slightly "busier" depending on your viewpoint.

I've got 2 Waterfords. One has Reynolds 753 and the other Reynolds 531. The 753 frame is noticabley stiffer. Even a non-racer like me can feel the difference. 853 doesn't feel much different than 753 but a lot stiffer than 531. IMO, there is a huge difference between generic 4130 and 853.

Tim