Those boats are aluminium hull ribs not aluminium floor sibs which wont fold.
Price is the only other advantage of a sib over a rib in that sibs are cheap. To get an aluminium hull rib down to the price of a sib then you would need to look for used. There are many makes of aluminium hull rib available now most will be made in china (our ribeye was) and if from a reputable maker then they will be fine just beware of Chinese companies selling direct as quality control is variable.
Plenty come onto the market which have seen little use hung on the back of cruisers as tenders which would make a good purchase.
I wouldnt be too stressed about buying new because after a season left in the water whatever you buy will be looking decidedly used.
The other advantage we found when we changed our tender from an excell sib to the ribeye rib was the rib was lighter. & in every other respect apart from folding & price it is a far better boat