Hi ducksterman,

If you have to stick to the correct recipe for both a Comparadun and a Parachute, there's no comparison, the Parachute hands down will give you hundreds more hatch matching possibilities than a Comparadun ever will.
You can change the post on a parachute to any color and lots of different materials, both natural or synthetic and foam. Hackle can be any color. You can tie the feather for the parachute concave side up to have it sit lower or the other way to ride higher. You can tie the parachute hackle using a piece of mono seperately and attach it to the underside of the fly for it to really ride high. You can use shorter hackle or longer hackle for different effects too. You can tie the tail with just about any material and tie it split, full, spread out etc. and it's still considered a parachute pattern. Bodies can be fat, thin, fuzzy, and any color too.
Camparaduns have to have a split tail made of micro fibbets or spade hackle, that's it. The wing can be any color, but has to be some form of short hollow coarse hair from a deer/elk etc. If the wing is ANYTHING but a 180 degree arc on the top part of the fly, it may be mistaken for a Haystack or something else.
I fully agree with RonMT about limiting yourself and never would, but if there wasn't any options, Parachutes.

Regards,

Mark