Using only my ears, I found that experimenting with 3 brands of horizontal WTW types (including my VP100) that there was negligible sound deficits in my room until past 30 degrees off axis.
While 'comb filtering' is certainly present in virtually all horizontal speaker designs, in the real world in most rooms it probably is minimal unless one gets way off axis. I didn't even bother experimenting with my new VP160 because I knew that there would be no or little degradation of sound within our listening area. Perhaps my odd shaped room helps as well...
TAM
