For that height and weight I'd say you'd be a good candidate for the 40's
I'm 5'10" and 180 pounds- and dropping.
I just got a pair of Mustang flap 30's and they are the best fins I've owned to date. Surface swimming is so much easier than with standard footpockets. I've only had them down to 10 meters so far, but am looking forward to hitting some depth once lakes clear up a bit this fall.
One interesting thing about the Mustang 30's is that they are shorter than my Flacon 30's. If the Mustang 80's are similar in size to a standard Falcon blade, instead of the longer Falcon 80 blades, then they should be easy enough to spear with.
Jon
