My experience is that they are a direct swap. All I needed to do was remove the existing shifters, brake levers and grips from the straight bars, swap them over and replace the same parts on the north roads. Holding the grips at the end of the bars tends to place you quite upright, but you have the option to move your hands forward onto the brake levers, front curves or even the flat central section to cheat the wind a little. You may want to get a slightly longer and/or flatter stem if you find they change your position too much. You can even run them upside down for a more aggressive style.

The bolt-on bar ends are quite versatile, since you can set them up pointing straight up, forward or anywhere in between. Another type of handlebar that offers a similar set up is the 'trekking' bar, also known as euro bars or butterfly bars. The only real issue is that you have to move your hands off the brake levers to get the most comfortable position.

I've seen pictures of a bike with a steering wheel before, though braking and shifting could be interesting with that setup...