Placement tips for Synergistic Research HTFs

I just bought 15 HTFs and will also be making about a dozen of Ozzie's homemade models.  While I will re-fresh myself with SR's placement tips, and I get that I will have to do some experimenting to tailor the HFT effect to MY listening room; are there any "Advanced HFT Placement Tips" some of you would like to share with us?  Something that might be overlooked by many of us?  Or maybe, just a good rule-of-thumb tip for someone just starting to use these?
The tips could be tips for bring out more highs, solidifying the bass response, placement hi vs low, in front of vs behind speakers, on side walls, at reflection points, behind the listener, on the ceiling above the equipment or above the listener, on the equipment.
Any ah-ha that you would like to share?  I would also be very interested in hearing from people using Magnapans.