There's a decent price difference between tier 3 and tier 5; we're a small agency with well under 50 servers. Our host has some 'service monitoring' baked in...am I wrong in thinking that Tier 3 is most resaonable for us?

We still get the network and process monitoring & alerts + rule templates.
No AppSumo plans include the transaction monitoring, lighthouse or screenshot tests.

Is there anything I'm missing, aside from the longer log retention, that would make T5 a better fit?