My understanding is that simply adding a stat or filter to the stat server config doesnt mean that it'll start calculating it. It'll only have an impact once the client application (URS, CCPulse, Pulse, WDE, etc.) subscribes to it, with or without the filters. So if you subscribe to Calls Answered on 10 VQs without a filter and then the same stat for the same VQs with a filter, you'll be suscribed to 20 statistics.
This page outlines memory calculations:
RTME Performance------------------------------
Jason McLennan
Commonwealth Bank of Australia
------------------------------
Original Message:
Sent: 05-16-2018 07:12
From: Jakub Němec
Subject: Limit of the filters and statistics
As I know there is no limit for filter definitions
------------------------------
Jakub Němec
Dimension Data Czech Republic s.r.o.
------------------------------