Buying LS3a or ASW20a? ~$25k cross country glider. Which one and why?

Maybe it's because im shopping a similar price range but it seems there's not much worth persuing among the aircraft you've listed in the U.S. Segelflug.de is what the europeans use for posting gliders for sale. You'll get a better value even with the transportation and exchange rate. Most of the gliders over here at that price point are pretty well neglected. On the other hand if you can live with a slightly lower performance glider, you can find Cirrus, Ls1, and Libelles at a lower price point in much better shape. For 20-30k you have to sacrifice at least one of the following: finish, customer support/parts, performance...forget about instrumentation it's not there.
Look on the bright side, glider manufacturers are buiding more motor gliders than pure these days and soaring in the States is in steep decline, soon we'll have a market flush with once expensive self launchers!