Right from a discussion internal reflexions (thanks to Ross Smith IV and Brian Day for their help on putting metrics down), here is the final statement.

Based on BES documentation :

http://docs.blackberry.com/en/admin/deliverables/8864/BlackBerry_Enterprise_Server_for_Microsoft_Exchange-5.0-US.pdf

We calculated that in summary based on their whitepaper for E2010:

IO Multiplication Factor: 2.0

Megacycle Multiplication Factor 1.5

Use these factors in your calculations, for example in the Exchange 2010 Storage Calculator.

Sam

[Please check the updated version of this post here]

For Windows 7 desktop users :

• Exclude all files present in  both below directories:
• %userprofile%\Application Data\Microsoft\Outlook
• %userprofile%\AppData\Local\Microsoft\Outlook

• Or exclude *.nk2, *.dat, *.srs, *.xml, *.otm, OutlPrnt, *.ost, *.tmp, *.obi, *.dat and *.oab files from these directories

For Exchange 2003, the Perfwiz is an HTML configuration file, that can be taken from Mike’s blog article specific for Exchange 2003.

For Exchange 2007 and 2010, just download the script from the following link :

http://experfwiz.codeplex.com/

It will set up performance counters from you and automatically select the best performance counters based on the roles of you Exchange servers !

Examples from Mike’s blog :

Remotely configure performance data collection on HUBServer between 2 dates or 2 hours (3rd October 7:00AM and 3rd October 11:00AM) with a collection interval of 15 seconds
.\experfwiz.ps1 -server HUBServerName -interval 15 -begin 10/03/2012 07:00:00" -end "10/03/2012 11:00:00" -filepath D:\Logs

Set duration to 4 hours, change interval to collect data every 5 seconds and set Data location to d:\Logs
.\experfwiz.ps1 -duration 04:00:00 -interval 5 -filepath D:\Logs

Add threads to the collection set
.\experfwiz.ps1 –threads

Stop Data collection
.\experfwiz.ps1 –stop

Create collection for all counters/instances.
.\experfwiz.ps1 –full

Example on my own server :

(Credits for this research goes to Sathya Narayanan, Microsoft Support Engineer)

Persistence : http://www.msexchange.org/articles_tutorials/exchange-server-2010/high-availability-recovery/load-balancing-exchange-2010-client-access-servers-using-hardware-load-balancer-solution-part1.html

Troubleshooting long running MAPI connections to Exchange Server 2010 through Network Load Balancers : http://support.microsoft.com/kb/2535656

How to setup an Exchange 2010 CAS Array to load balance MAPI : http://blogs.technet.com/b/ucedsg/archive/2009/12/06/how-to-setup-an-exchange-2010-cas-array-to-load-balance-mapi.aspx

Microsoft Exchange 2010 CAS Array – Steps and Recommendations : http://blogs.technet.com/b/omers/archive/2010/10/11/microsoft-exchange-2010-cas-array-steps-and-recommendations.aspx

Configure Static RPC Ports on an Exchange 2010 Client Access Server : http://social.technet.microsoft.com/wiki/contents/articles/864.configure-static-rpc-ports-on-an-exchange-2010-client-access-server.aspx

• The security update catalog file, wsusscn2.cab (http://go.microsoft.com/fwlink/?LinkId=76054)
  
• The Windows Update Redistribution Catalog, wuredist.cab (http://update.microsoft.com/redist/wuredist.cab)
  
• The authorization catalog file, muauth.cab (http://go.microsoft.com/fwlink/?LinkId=43266)

Where to copy them ?

in Windows Server 2003 :

%userprofile%\Local Settings\Application Data\Microsoft\MBSA\Cache

in Windows Server 2008 :

%userprofile%\appdata\local\Microsoft\MBSA\Cache