We'd use it to get close to exposed rocky shores, into little tiny pocket beaches, up creeks, etc, so I can go photographing. The kind of places we used to get to with our sea kayaks.
Given the rocky, barnacle and oyster encrusted shores in this part of the world, a fabric boat would be at the very bottom of my list of choices for a dinghy/shore/utility boat. In fact a fabric boat wouldn't even be on the list, particularly if one of my stated objectives was to work around and on our shorelines.
At the top of my list would be the Bullfrog (they are available in sizes larger than 10' although the bigger ones, while popular, are butt-ugly). Below that would be things like a larger Livingston (to get more freeboard), a small Boston Whaler, and so on.
As to speed, a Bullfrog, Whaler, or even a larger Livingston can get up and scoot. While this is not recommended, a friend of Carey's bought a 10' Bullfrog and mounted a 40 or 50 hp outboard on it (maximum motor size for this boat is 15 or 20 hp). He then fabricated a stand-up helm consol for the boat. He used it for awhile to "commute" from Bellingham to Friday Harbor in the San Juans to visit his girlfriend. IIRC the boat would exceed 50 mph on decent water.
But we have known or met a sufficient number of people over the years who have experienced damage to their fabric dinghies on our shorelines to know that we would never even consider one for this area unless we knew that virtually all our dinghy use would be to docks or sandy/gravel beaches. An RIB is a bit better than a straight inflatable in this regard, but where the shores are rocky, and particularly where water motion can shove the boat around against the shoreline, even an RIB can suffer damage to its tubes.
And a note about aluminum dinghies (or boats with aluminum bottoms). If you carry an aluminum dinghy in a position where soot from the diesel exhaust of your boat can collect and build up on the bottom of the dinghy, you may be in for a rude awakening. Diesel soot, in combination with moisture, creates a wonderful acid which will eat into and pinhole aluminum. This happened to Carey and the dinghy he bought to replace their failing inflatable. This dinghy was a Duroboat, and because it did not tow well he designed and had fabricated the davits pictured in my earlier post. Suspended directly over the boats exhaust, it wasn't long before his new Duroboat had a covering of soot on its bottom.
One day a couple of years after buying the Duroboat, Carey was out in it when he noticed water was beginning to puddle in the bottom. He eventually traced it to a few leaks in the aluminum skin. Puzzled as to why the bottom skin was leaking, he and a friend got another dinghy and inspected the bottom of the Duroboat when it was hanging from its davits. What they found was pretty amazing. The whole bottom and keel of the Duroboat in the vicinity of his lobsterboat's centerline exhaust was pitted, eaten away, and starting to pinhole. Further investigation turned up the business about diesel soot, moisture, and acid.
There were other things he didn't like about the Duroboat so he had it repaired and then sold it and replaced it with the Bullfrog. The Bullfrog also has an aluminum bottom but unlike the Duroboat's raw aluminum bottom the Bullfrog's V-bottom panel is powder coated and it's easily replaceable.
So, the moral of the story is if you buy an aluminum dinghy or a dinghy with an aluminum bottom, don't carry it on the boat in such a way that diesel exhaust soot can build up on it. Or if you have no other choice, paint or powder coat the aluminum.