Change SQL minimum Query memory setting

We are on SQL Server 2008 R2 enterprise edition and there is 128GB physical RAM installed on production server .The max SQL memory is setup to 112GB and the current setting of SQL minimum Query memory is 4096 KB .Recently, our production SQL server was evaluated by Microsoft MPV SQL DBA and he recommends to change the setting of minimum Query memory from 4096 to default 1024kb.

Now, I would like to measure SQL performance before I will change the minimum Query memory to 1024 KB and I also would like to measure the SQL performance after the change, but I am not sure what performance counters should I measure before and after the change? What is the best technique should I use to compare the results to prove that the change is beneficial and how much SQL performance is improved the change ?

Would someone please guide me from where do I start ?

Thanks ,

Daizy