From a router attached to ICONZ's network, 192.88.99.1 is in Poland, so your encapsulated packets are crossing two oceans. From a router attached to TCL's network, 192.88.99.1 is in Boston. Neither of these are obviously better choices than the usual suspects on the west coast of the US, or AARNet in Australia.
I was going to say in my previous email but forgot, I should pimp out tr some more: http://tr.meta.net.nz/output/2005-02-27_11:48_192.88.99.1.png That shows more or less where everyone ends up finding their favorite 6to4 anycast relay server. It's interesting that there is a /lot/ of variation as to who finds what. Also several places take quite a little tour to find their anycast routers. Usual disclaimers apply to tr graphs (AS# information is kinda quirky, I only have tr drones in some places, etc).