There is no Warp3D 4.3.
The 4.3x permedia driver was so enumerated by me so I could keep several revisions privately on my system during testing and development. Several people tested this version for me which improves raw rasterization performance (especially for vertex array methods) and implementation level over the stock 4.2 driver. However, there are various problems with some existing versions of MiniGL (which access the W3D_Context structure directly and make other assumptions that it shouldn't) that tend to make the driver rather pointless as many existing games tend to break, some quite spectacularly.
Oddly, however, some work just fine - No main problems here with GLQuakeWOS or Heretic 2 with this driver for example.
-edit-
It's all due for an update but alas I have hardly had no time to even boot my amiga in the last six months, let alone actually code on it.