Originally Posted by TryHard

I'm not Jilles, but I did a back to back last weekend between split blocks and one-pieces. If your using a standard top-deck (i.e. not cutting the braces), then you'll get more overall grip, with a balance shift to the front... in other words, more steering!
I find the cut topdeck tends to shift the balance back a little to the rear of the car (more traction), but with the split blocks and cut top deck, you still get a little more steering.

Hopefully Jilles can comment on this too, he's got a lot more experience running that setup (and better thumbs!) than I have

HiH
Ed