PMAX or SHOPPING?

Good afternoon, everyone. I have a question and would love your help...

For a new account with no conversions yet, is a Standard Shopping campaign \*really\* the best starting point before launching a Performance Max (PMax) campaign? I’m running ads for a watch e-commerce store targeting the US. I have a Standard Shopping campaign running with a $0.50 manual CPC; it’s been active for 4 days with a $22 daily budget and zero conversions so far—just 8 "add to carts" and 2 checkouts... Would I get better performance if I launched a PMax campaign without assets? I’d turn off the Shopping campaign and run only the PMax campaign (set to "Maximize Conversions") with a higher budget. With all due respect, the store looks amazing and is very well put together... if anyone can genuinely help, I can share the link.