No firmware is perfect. Even with SE11, the 3560's 64MB DRAM (128MB on -G models) means:
This file, c3560-ipservicesk9-mz.150-2.SE11.bin , is a Cisco IOS software image for the Catalyst 3560 series c3560ipservicesk9mz1502se11bin
Switch# copy running-config tftp: # Provide TFTP server IP and filename (e.g., 3560-backup-config.txt) No firmware is perfect