I have a few questions that I have noticed about the plugin.

Do you find if you put in a distance of 10,000 it stops finding nodes that it would have found on 1000?

Also I've noticed the radius doesn't seem to pair up with the distance always. I have a node that returns 277 as the distance but I have to have a radius of 607 before it is found. Do you have this sort of problem?

Sometimes even with a lat and long some nodes don't appear in the results. Again have you noticed it missing some nodes it should have found for any reason?

This is all done directly to solr so I know it's not your module but if I can't get it to return the right things the module will not work either :(