Query Monitor (QM) is available by default on all production and development sites and you can add the
view_query_monitor capability to any role that should have access. Alternatively you can filter
wpcom_vip_qm_enable directly in your query-monitor.php file.
Either method is fine to use. The only thing to be careful of is disabling access for VIP Support. (For example, if you filtered
wpcom_vip_qm_enable to only return
true for your team, we would no longer be able to use the query monitor on the site.)
In addition to this, you can set an authentication cookie which allows you to view Query Monitor output when you’re not logged in (or if you’re logged in as a user without the
view_query_monitor capability). See the bottom of Query Monitor’s output for details.