It would be helpful to know just what it is you are intending to install in that VM. For example, 8GB won't be enough if you intend to, say, install Mint 14 KDE and update KDE itself to a later version. But then, maybe you intend to install LMDE, or MATE or Cinnamon edition. Only you know so far.
Mint Testing Team & Mint Donor #3606
KDE 4.14.2, custom preemptive kernel 3.16.5,
Intel i7 4820K @ 4.7GHz, 32GB Corsair Vengeance Pro
3122MHz XMP, 4 Samsung 840 PRO 512GB SSDs in
RAID0, 6TB HW RAID10, 3 x 24" Samsung UlHD,