We're not the only ones to think that there should be an alternative to inflatables and RIBs. There are also (with apologies for any that we've missed):

(1) FOLDING DINGHIES

Three main manufacturers we know of: Portabote, Seahopper and Stowaway. All fold up into a package that is fairly flat, but still the same length as (or slightly longer than) the assembled boat. You need to find somewhere to put this - most people end up tying them to the guardrails at the bow of their main boat, which is sort of OK most of the time but far from ideal in rough weather. There is also a large pile of thwarts etc which have to be taken out/put back in during the process of dismantling/assembly. Portabotes are made from a plastic board material, Seahoppers are made from varnished plywood, and Stowaways from fibreglass panels. The main problem seems to be making them stiff enough - see what Sailing Today magazine said, below. And in the case of the Seahopper, keeping the varnish on the wood when you drag it up beaches and leave it alongside quays (scratches, besides being heartbreaking, will let the water in).

"… the hull shape leaves a lot to be desired, both aesthetically and hydrodynamically. It is, not to put too fine a point on it, determined entirely by what can be folded and unfolded. Almost inevitably, this doesn't produce a shape that is that easy to row. It is further hampered by the fact that the hull sides and bottom flex as you apply any pressure to the oars or shift your weight... not much better than an inflatable to row."
Test of Portabote 12, Sailing Today Magazine July 2003

"...She's no beauty, takes a long time to deploy and is very heavy"
Test of Stowaway K2, YACHTING MONTHLY December 2008

There are some other folding dinghies about, mostly in plan or kit form. If you've got somewhere to store a long, relatively thin package and all the other components, it's definitely an option but we havent yet seen one that is pretty...

(2) HARD DINGHIES

The old-fashioned approach yes, but one that worked fine until the latter part of the 20th century. They are tough, durable, relatively easy to fix, and designed right will be a delight to row. But of course the problem here is stowage of one that is big enough to be useful as a tender. Which is why you need a Nestaway nesting dinghy, or sectional boat! And even if you do have space for a full-size hard dinghy, a Nestaway can give you back half of it when you want it, on long ocean voyages for example.

By far the most common material for hard dinghies is glassfibre, followed by various forms of plastic - injection-moulded, roto-moulded etc. Some astonishing claims are made for the longevity of plastic but in our experience they do all dent or scratch (most quite easily, although not usually catastrophically), and the panel stiffness (which makes a good rowing or sailing boat) is relatively low. Most therefore seem to end up quite thick, and heavy. Glassfibre is stiffer and tends to look better (shiny and smooth); whilst it is very durable (virtually all the yachts are made from it!), you can chip the gelcoat, but it is also easy to repair (plastics tend to be quite specialist). You might also find the odd aluminium dinghy and of course there is wood which is light and strong but must be protected from the elements (eg by epoxy sheathing).

(3) KAYAKS/CANOES

If you have a good place to store a folding dinghy - ie something long and thin - a couple of kayaks/canoes might be an alternative.

 TEN TENDERS TESTED - Yachting Monthly, December 2008