Too late for reply but I guess (by know you know this) that your current specs are more than enough.
What I have at home is an old desktop with the following specs:
AMD Phenom II X4 840
8GB Ram
500 GB HDD
Builtin Graphics
Still I was able to run an environment that allowed me to play around with features in preparation for my 510 exam.
Here's my lab setup
Network (edit VMware Workstation Virtual Network Editor)
192.168.0.0/24 - Management Network - Bridge - vmnic0
192.168.8.0/24 - Storage Network - Host Only - vmnic1
192.168.18.0/24 - vMotion Network - VMNet 2 -vmnic2
Redundancy - Management Network - Bridge - vmnic3
prodnet - VM Port Group - VMnet 3 - vmnic4
Shared Storage
vmwarevolume My iSCSI Volume 4096 MB iSCSI
Virtual Machines
FLR1 - Open Filer 2.99.1
192.168.8.4
VC2 - vCenter Server Appliance 5.1
192.168.0.5
ESXi1 - vSphere ESXi Hypervisor 5.1
192.168.0.6
192.168.8.6/9
192.168.18.6
ESXi2 - vSphere ESXi Hypervisor 5.1
192.168.0.7
192.168.8.7/9
192.168.18.7
Summary
DRS and vMotion in action
vCenter as an appliance (tried using the normal vCenter but its slowing my system down)
Openfiler for shared storage.