Evening,
Syslog is prefered but VMware has provided a syslog collector on the vcenter install disk that can be installed on any windows host or on your vcenter. I cannot count the number of times I have had hosts psod and the logs lost... thank goodness for the syslog that collects right up to the crash. It's not required but it's a really good idea without any real cost since you can use your vcenter host.
Here is a article on how to install it:
Setting up the ESXi Syslog Collector | VMware vSphere Blog - VMware Blogs
Thanks