I remember using he.net year ago for their IPv6 tunnels years ago, and have painful memories of configuring it, both on the router and to share to the subnets on my home LAN. Not this time. Years ago, I had Comcast Business Internet service, which along with providing a static IPv4 address, provided IPv6 connectivity. Not only just a single /128, but a whole /56 if you asked for it. After spending days/weeks configuring both dhcp client and servers for prefix delegation, and slaac/rtadvd to hand out addresses to my various LAN segments, I was in business.