I put a Shimano coaster brake hub on my 99 & it works great. I don't have to press hard with the pedals at all to get the back wheel to lock up. I can't ask for more than that & it fits without any changes except for a little work to the brake arm. I posted about the brake arm thing here a month or so back. Also they're only $20. or $30. I like to keep things simple but efficient.
Jay