I'm running Ubercart 7.x-3.1 and rolled on the "Ajax-ify attribute option" patch #51 from here. It works and price gets updated. But I think I found a bug and the last message in that thread says to post new topics since its now rolled into UC itself.
I have multiple attributes on each item and they are all set as "radio buttons" with 3-5 options on each attribute. They all have a default value and are not "required".
If I start selecting multiple attributes (not multiple options in an attribute! but actual different attributes rapidly one after another) it seems like all of the attributes are getting selected and throbber is rotating on all of them. But once they actually finish only the last clicked attribute is selected and all others are set to the default value. Even if I individually selected different option for different attributes and am now changing multiple attributes to a different value it will still reset back to default.
Please let me know if you need additional information to reproduce.