Well I'm biased, I'm a dealer for www.tracksplus.com but for floatation in mud our tracks have the benifit of not being overly heavy.
A set for you 773 weights @ 450lbs. we also have a shoe with alot of area, which helps keep you up.
They are constucted from a vary hard steel, so they don't require the extra 400 lbs to make them strong enough. I have over 400 hours on my personal set, and guaging pin and track wear, I will see in excess of 1000 hours for a track that is 1/2 the price of some.
The reduced weight also make them a lot nice to install and remove. Think about pull the ends of 500 lbs of steel together on top of you tires and getting the bolts in, in a mud hole if you have a flat.
My .02
Ken
www.skidsteer.ca