I've been having a good time with 90 degree transitions lately. I slightly modified it to simulate a longer shot on one side, using a 1/3 scale metric on one side and a 1/6 classic on the other, with a distance of 3ish yards... It open my eyes to some flaws in my draw and transitions. I started with an easy par of 2.2 and worked it down all the way to 1.5, where I pretty much topped out. I found myself overaiming on the easy target and then transitioning slower on the smaller classic. Each time I dropped the par time I shot the array from both directions, so I drew to an easy shot or a harder one. It was initially easier to draw on the 1/6 and make a snappy transition to the easier 1/3 scale metric.
As the par got tighter and tighter I found I had to just let it happen on the closer target if I was going to make the time. I found it was much easier to call two As on the 1/3 target than I was allowing. On the other hand, my eyes were transitioning very well to the bigger target when I drew to the more difficult target, but the draw forced me to let it settle a bit. Once I got more aggressive on the easier draw target, I had to work on getting my eyes to lock on the A zone of the 1/6 target fast if I wanted to have any hope of making the par time. Once this was sorted out, and the par time was as fast as I could call shots without being overwhelmed (1.5s), I ended up being better when starting on the near target and transitioning to the 1/6 scale "hard target."
Dry-fire is so much more fun when you feel productive.