The tank and it's location was why I decided against propane. The loss in power was another factor, and when combined with the fact it isn't nearly as cheap as it used to be I couldn't think of a good reason to use it.
Locating a tank in a K5 is kinda tough. You're more or less stuck putting it where the old gas tank was, and that's a little too vulnerable to rocks for my liking.
Rene