6rd is pretty awful, generally, and I couldn't get Centurylink's to work last time I tried. I appreciate the notes and will take a look, thank you.
(One big problem I've experienced in the past is that any time you configure both IPv6 and IPv4, all programs prefer IPv6. But tunneled IPv6 has much worse performance than the native IPv4, so you really want applications to prefer IPv4 in a tunneled v6 environment.)
I still use Hurricane Electric tunnels fir my v6 and ping times/throughout are so close as to be in the noise for most everything. It probably helps that I'm using a tunnel endpoint literally 10 miles from my house however.
My IPv4 ping times to Google and Facebook are 2.6 milliseconds. I suspect any HE tunnel is going to be worse than that (in a statistically significant sense). I don't know that latency would necessarily be perceptible the majority of the time, but I strongly suspect outliers would be worse and more frequent.
Also, I doubt HE's ipv6 tunnel is going to carry anything close to 1Gbps for me for free ;-).
(One big problem I've experienced in the past is that any time you configure both IPv6 and IPv4, all programs prefer IPv6. But tunneled IPv6 has much worse performance than the native IPv4, so you really want applications to prefer IPv4 in a tunneled v6 environment.)