That's really the golden ticket there. With a seed box there's no chance your VPN fails (download stuff on the box directly, you'll have a secure shell and KVM). That can be a real problem with normal vpns if not configured properly (you need to force traffic through the VPN and reject on failure, while most default to a fail back and will expose your IP.)

If you have got enough local storage capacity then a regular vpn is still by far the cheapest option. Also if you only download from private trackers you might not even need a VPN, since ip trolls tend to stick to public trackers.