GSG, I can comment on this issue in that I own and have converted both a Redline and a Pyranha Burn. In fact, I paddled the Redline today. It is my go-to river runner and surfer and I have been paddling it for about 12 years. I use the Burn for creeks and for big water where I don't want unexpected squirts from the rear end. I'm 5'10 1/2" and just short of 190 lbs. with a 32 inch inseam. Here is the tidbit you might find interesting.
![:-?](./images/smilies/icon_confused.gif)
I actually find the Redline more comfortable to be in than the Burn, even though my seat is way lower in the Redline. My Redline seat is 6 1/4 in off the floor. I started my Burn seat at 6 1/2 in, but have raised it to about 7 inches, because I couldn't tolerate the lower seat. I have ankle supports in both boats. It may be an artifact of the way I did the conversion, but the Redline is more comfortable, and I am hardly ever in a rush to get out and stretch my legs. I haven't measured it, but it seems that my knees are more spread out in the Burn than in the Redline, which would lead one to believe that it would be more comfortable but that hasn't been the case.
I love the Burn for its predictability, its re-surfacing, its ease of rolling, and go to it whenever the pucker-factor gets larger, but I don't go to it for comfort. It is not bad in that regard. Most of my friends are amazed at how long I can stay put in either boat. It is just less comfortable for my particular body, even with a higher seat and most likely a greater knee spread.
My avatar is me in the Redline.
Good luck with whatever decision you make.
Jack