What is the need for this VPN in the first instance? You mention security, what are you trying to secure? If they're just browsing Facebook or whatever you're probably over engineering things.
Not really, VPNs should be the norm with all the government snooping included in the IP act.
By having a deadbolt on my front door I'm probably overengineering things, surely nobody would try to break in....
That said, I gave up on using VPN for everything from home, too many forums etc block VPN and Hosting IP ranges, and none of the VPN providers can sustain decent throughput, I've yet to try one that will give me over about 60mbit.