RHS. Loop for easier and more RHS.
Straight for more control and precision.
Look at your serve, or better, your overhead. Overhead, if you're tentative, you shorten the loop, almost to a high volley stroke. If you're confident, full loop like a serve.
Think of this. Your serve would be more precise if you laid your wrist back, held a JayBerger early trophy, and hit the ball. It would have less power.