People recommend 500GB size on non-VAAI storage because there is high possibility that you will have larger number of VMs in are larger storage to utilize all the space. If you have too many VMs running in a VMFS storage, you will run in to performance issues.
However, not all environment is same. You need to get average size of your VM and think about how many VMs you want to have in your LUN. For the argument sake, let's say average VM size is about 200GB and people are consumming most of the allocated storage space in the VM. You don't want to have 500GB LUN in this case. You may want to have 2TB LUN to avoid provisioning too many smaller LUN.
David