I spent over an hour with the carseat tech at my local baby store this afternoon, and he was adamant that any PROPERLY installed carseat is hard to put in. No matter what make or manufactur. And if it's easy, you've probably missed something. And esepcially the Britax and Radian seats - he didn't recommend anyone install them other than a CPST.
We've installed our boulevard in numerous cars now without a problem.