Any phenidone based developer will do. If cost were no object I would use Tri-X at 800 with undiluted Ilford Microphen. If I had to develop a lot of Tri-X at 800 I would probably choose Clayton F60 and dilute it 1:9. The faster-than-400 films will give better shadow detail but cost more. Fuji Neopan 1600 is out of production. Kodak TMZ may or may not still be made. I prefer TMZ to Ilford Delta 3200 but I hope the Ilford product remains in production if TMZ doesn't. When I pushed film more often my favorite developer was Ethol UFG. I still keep UFG around, just in case. I wish 2475 and 2484 were still made. I had fun with them.