OK, here's my thoughts. I really don't think you'll load up enough to matter at the track. If you run it a lot at home however, you'll load it up. I ran power valves in my sbc with a 950hp for just that reason. Since I went bigblock and a Dominator, I hardly ever fire it up at home. Just to unload and warm it for oil changes and valve adjustments, so I don't run pv's.
The only downside I can see is the potential for a backfire damaging a pv or just one failing. They really aren't necessary on a race car if you can resist the urge to annoy your neighbors!!