Backflow preventer (protecting potable water supply)

I seem to see three types of backflow preventers:
1. valve + vacuum breaker 2. double-check-valves 3. double-check-valves + pressure regulator
If I don't need or want pressure regulation how do you compare 1 vs 2 above?
This would be for lawn irrigation or water-powered sump pump.
Examples:
https://www.homedepot.com/p/Zurn-3-4-in-Brass-FIP-x-FIP-Pressure-Vacuum-Breaker-Backflow-Preventer-Check-Valve-34-720A/100197627
https://www.homedepot.com/p/Febco-3-4-in-Bronze-Double-Check-Valve-Assembly-3-4-850/205888731
https://www.homedepot.com/p/Apollo-3-4-in-Lead-Free-Bronze-FIP-Reduced-Pressure-Backflow-Preventer-4ALF204A2F/307723094
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On 1/12/2019 10:14 PM, Davej wrote:

If you've not done so already, check your local codes to see if they specify one type. Some do not allow double check, others do.
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On Saturday, January 12, 2019 at 10:34:21 PM UTC-6, Ed Pawlowski wrote:

Will do. I think the vacuum-breaker approach seems more logical.
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On Sunday, January 13, 2019 at 1:33:48 PM UTC-5, Davej wrote:

That's what's used here, NJ for irrigation connection. I would bet it's probably part of the widely used national plumbing code.
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