I have a Honwave t35 the little brother of the sib in question on this thread.
I was advised when purchasing my sib not to go for the larger / wider t40 as the wider floor pan and bigger tubes made the set up more susceptible to broken floor components.
I'm under no illusions that my Honwave is built to a budget!
Mines has four years service under its belt with no signs of wear and tear despite being out on many a high sea.
If the floor buckled and horse shoed on me tomorrow I would not feel that I had been short changed for th 800 quid I had paid for her 4 years ago!
I think the larger you go with the aluminium floored budget Sibs the higher the probability there is of a floor components failure!
As the saying goes the bigger they are the harder they fall.
Once I need to go 4 metre I will bite the bullet and get a small Rib