What does Exchange HealthSet property values like Priority & HA mean ?

Hello Guys,

Can some one help me understand what does the below highlighted properties mean and what would be the impact ?

PSComputerName          : testexch01.ram.com

RunspaceId              : 081e77d0-78f9-4de5-ab52-6cfa78c030ca

PSShowComputerName      : False

Server                  : testexch01

CurrentHealthSetState   : NotApplicable

Name                    : AuditLogSearchCompletedWithErrorsMonitor

TargetResource          : Compliance

HealthSetName           : Compliance

HealthGroupName         : CustomerTouchPoints

AlertValue              : Healthy

FirstAlertObservedTime  : 1/1/0001 12:00:00 AM

Description             :

IsHaImpacting           : False

RecurranceInterval      : 3600

DefinitionCreatedTime   : 1/26/2016 11:50:45 AM

HealthSetDescription    :

ServerComponentName     : None

LastTransitionTime      : 1/9/2015 11:49:51 AM

LastExecutionTime       : 2/5/2016 1:49:59 AM

LastExecutionResult     : Succeeded

ResultId                : 180800748

WorkItemId              : 1

IsStale                 : False

Error                   :

Exception               :

IsNotified              : False

LastFailedProbeId       : -1

LastFailedProbeResultId : -1

ServicePriority         : 2

Identity                : Compliance\AuditLogSearchCompletedWithErrorsMonitor\Compliance

IsValid                 : True

ObjectState             : New

Below is what I would like to know.

1) What  is IsHAImpacting ? I see only two identities have marked to True and rest all to False when I ran Get-ServerHealth for server.

2) What is Service Priority mean ? Critical things would have 0 or 2 ? I mean lowest means the most critical one or the highest means the most critical one ?

3) Finally, what role does the above two play or help when are moving DBs from server to server ? Does Exchange Active Manager even care about this when it's performing BCSS ?

Thank you in advance.