Dunno where you live but I know that houseboats built for charter in South
Australian waters (River Murray mainly), must be built "under survey". This
means mainly safety specifications such as pontoons built with several
seperate chambers in case of rupture etc, quality of welding, regular out of
water inspections & so on.
I think there are requirement as well for shape so as to minimise river bank
erosion.
Now in my mind, if it reduces the "bow wave" & "wash", then it would also be
more effecient.
I'd look up & maybe email some of the construction companies & get some
advice from them?
Many of these huge houseboats only use twin 25hp outboards or similar.



"Tim" wrote in message
oups.com...

jamesgangnc wrote:

Tim

In a real world test there would be no noticeable performance
advantages or disadvantages because of differences in the shapes of
pontoons on pontoon boats. Find the one that is the size you want,
with the features you want, at the price you want to pay and forget
about what shape it's pontoons are. If you care about performance you
need to stop looking at pontoon boats.

That's sort of what I was thinking. and by meaning "performance" I
wasn't talking about stuff like speed and handling, but rather
operational economy. I thought it was odd that there that many
varient's in tube designs, though.