If you check torque on the adjustable hold bolts every couple of rides, you won't have issues with them coming out. My holds came loose maybe once this year, while we were in Havasu, but I was riding for hours each day and didn't bother to check them once.
The reason we went with the adjustable format is every likes foot holds different. We'd spend weeks adding/ removing turf to get the standard footholds how we wanted, and they still weren't perfect. With adjustables, you easily lower or raise them to where you want, torque the bolts and they don't move. You only mess with them the first couple of rides, but once you get them where you want, they're dialed, and your tray does look like an avalanche of turf.