Historically I'd say Seimitsu LS-32 or LS-40 as I read they were the levers most commonly installed in Neo Geo cabs in Japan (not that I can back that up).
Today, I like modded Sanwa JLFs. I personally like the v2 OTTO DIY kits.
Also been seeing some very good things about the new Sanwa JLX.
OTTO is where it's at for me as well. Using the V5 with a V4 steel core and adjustable silent switches from JLF-TPML. Probably won't go back to standard Sanwa or Seimitsu.