Michael,
Did you evaluate SWISH-E? If so, why did you choose SWISH++ over SWISH-E?
I must admit that though SWISH-E is rumoured to die on indexing at times, I am nonplussed by SWISH++ requirement on using C++ and making me (still running RH 6.1) have to upgrade various gcc libs.
Beyond that however, SWISH-E looks to have better search capabilities and better indexing features, including an Intermedia-ish way to index right out of the database.