If you're going to the trouble and added expense of main studs, this is also the time to add a stud girdle. I agree, under 500 hp, none of it is needed.
When I built my current engine I went with main studs, but not the girdle. One season of racing, and I found #2 main cap broke in half. Luckily, I found it before anything else got damaged. This engine made approx 580 hp.

Brian