This is the flattest I've gotten out of it, and am quite happy with it. I did some bright star testing with the "halo-free" Astronomik NB filters, and there were some halos there, but could be attributed to the Orion Flattener. I'll have to test without to be sure.
I "accidentally" ordered the Televue TRF-2008 the other night in a fit of retail-therapy-rage

Will see how it goes, keeping options open at the moment.