That's great to know, that two Titan65's can nest into one another. They're also light, which is helpful. How were they to install? They're also not expensive, relatively speaking for a seat that goes to 65lbs.

Another version when traveling with a double stroller would be to put the two nested seats in one half of the double stroller, leaving the other seat free for a child to ride in.

Using the tether straps is a good idea.