There's also Mesh Mode (activated by Create Meshes in the build menu), which does not generate BSP at all no matter which version you use. This should save you compile time, and ABT is used when rendering the level. Using Simple Map still generates the BSP tree if Create Meshes is off.

I was in the understanding that the BSP tree generated by non-Pro A7s was actually an A6 version... but then I guess this is atually not the case? I've been trying to find out how one would "activate" the A7 BSP and what the actual changes would be compared to A6. I found very little on this subject.