Do I have a stack of 3548's connected wi the gigstack connectors. DO I need to have STP turned on the switches? What does it give me, and what do I loose by turning it off?
I would never turn off spanning tree . What do you lose? Layer 2 protection against layer 2 loops whether it be configured or unintentional like someone plugging in a handy dandy home router in your network and accidently causing a loop . You will see how short a time a network can go down if this happens .