Migration from M1000 chassis and from Old Equal array - Questions

Hello's

We are planning a migration from an old M1000 to a newer M1000. In addition, we will be migrating from an old PS array to a newer one. The environment is 100% virtual - Vmware. There also exist storage side Snapshots for several of the volumes.
Here are my questions.

1. Whether to use vmwares storage vmotion for the migration (which would move both the vm to the new M1000 as well as move the storage to the new array. OR
2. Add the new array to the group, evacuate the older array which would copy data from the old array to the new array and then after the Evac is done, vmotion the VM's to the new array.

What is the most efficient way of carrying out this migration?

thanks ,

V.