I ended up selling my 43 because I just didn't shoot it as well as my other single stack 9's, but when I was reloading for it I found medium burn rate powders to work best overall in the pistol.
For Winchester 115 N-JHP and Speer 115 GDHP, 5.7gr CFE Pistol with CCI SP primer and Federal FC case @ 1.125" proved to be good accurate loads.
Also Xtreme plated 115 RN in Federal FC case, CCI SP, 5.3gr CFE Pistol, 1.105" OAL
For 124 I liked Power Pistol the best, specifically either Winchester 124 FMJ or Hornady XTP. 6.5gr Power Pistol with a 124 XTP in Hornady and UMC brass, CCI SP primers loaded at 1.105" For the 124 FMJ i seat to 1.110" OAL and run 6.3gr Power Pistol, all else the same.
The hands down best 147 I loaded for the little G43 was 3.1gr TiteGroup with a 147 From ZERO bullets, FC & RP brass, CCI SP, loaded to 1.155" OAL. Soft shooting, superbly accurate and very fast follow up shots. I currently still load this for my Other little 9mms.
My second favorite was 5.6gr Power Pistol and a 147 XTP @ 1.141"
These loads all did well in my 43 while I had it and continue to do well in my M&P Shield, Sig 938 and KelTec P11.