I like the idea of swapping out the turrets, but for the most part I found it easier to press on in the game if I avoided trying to navigate the bullets to perform a swap. Plus with the second falling block on the screen only when the first is so near to the bottom, if I wasn't sure the same color was coming it might be too late to shoot the first block and bail on the swap. I might be more comfortable with that process if things were scaled down and I could see multiple blocks, despite the extra streams of bullets.