Learning the v3i taught me a lot about the detector sweep speeds. With 8 filter combos to choose from, you need to vary sweep speed. For greatest separation, id pick 12Hz, speed up recovery and reduce SAT. This requires a pretty fast sweep as tested on the nail board to hit cleanly. A slower sweep reduces positive hits. These settings do not allow for greater depth.

If i want to gain depth, i switch to 5 Hz and swing slowly. I reduce recovery speed and SAT. This is better aligned to deeper targets with limited trash.

So, knowing your detectors filter design will help dictate proper swing speed...which you can determine more pragmatically as Rich described. Coil size also needs to be considered.

I know....awfully technical for 'how fast is too fast.

Gregg thought i was cutting grass on an outing last spring, but thst is what the settings required.

Zincoln