Another vote for the TMK. Only one deer for me so far with it, my daughter killed her first deer this year with it at 250, and tissue damage was impressive. Pass through, 3-4" wound channel that if you told me it came from any .308 or Creedmoor sized cartridge I would believe it.
Full disclosure, the deer did run further than I expected when hit, and I was surprised at how much tissue damage I found given the long-ish (200+ yard) run. The shot was about 2-3" behind the crease, so back half of the lungs but it stayed well in front of the diaphragm.
Lots and lots of great reports on that rokslide thread. People reporting solid results anywhere from sub 1800fps impacts all the way up to .22 Creedmoor velocity, so I think that BR should be a sweetheart with that bullet! 400 might be further than I would be confident at .223 MV's, but a 200-300 fps bump should get you there.
I've seen lots of mixed results from the non tipped SMK. Some great great performance, but seems far less consistent and reliable terminal performance.