One more thought and I will leave it alone.

I have noticed that it can be very difficult to shift the t20 when my Max IV is in tough terrain. It is almost impossible to rock the machine enough to get the gears to mesh up when you are in very spongy material that resists rolling. It can be done, but I have sometimes felt like getting out and pushing it back and forth to get it done. I think an 8x8 version would add to this problem. Based on what I have seen about split shifting the t20, I think a heavier machine would need to come stock with split shifting. This would help bring back some of the nimbleness of the smaller machines and make the thing easier to get into gear.