We used a similar model extensively in the Med aboard the boat I crewed on. For some reason I thought it was called the "Redcrest", but I could be mistaken.
We only towed it for short hops. Anything longer than 30 n.m. or so we would deflate it and stow it -- which is to say, most of the time. With practice, and the big manual foot pump that comes with it, we were able to get it set-up and ready to go fairly quickly. Same with deflating and stowing.
We would row that dinghy for shorter distances in smaller anchorages. It rowed okay. For longer distances, we'd affix the motor mount and had a little British Seagull putt putt that pushed it along. Not quickly, though. With that fabric floor, I would say there's no planing in these no matter how much hp you added. My guess is 2 hp gets this to "hull speed" and anything more would be wasted unless you have huge currents.
Once while towing (I was not aboard at the time) in heavier seas/air, the dinghy lifted off, spun around a few times, and the painter separated. It went tumbling downwind faster than the owner could maneuver to recover it. The owner did replace it with the same model -- so that says something I guess.
Ignore the next two paragraphs if you're not interested in "commentary".
All that said, and having perused your "big trip" itinerary and knowing a bit about what it is like to sail with young kids.... I'm not sure this is the style dinghy I would want for the sort of family sailing I and you do. The extra step of needing to inflate/deflate is something I wanted to avoid when sailing with my family. There's just so much else going on, that eliminating steps like that can make the outings more enjoyable.
Also, as you probably know, I'm a big proponent of teaching kids to row and sail in little dinghies at anchor. If you ask my kids today, they will tell you this is the aspect of cruising they enjoy most -- getting out on their own and exploring in the dinghies. In my opinion, hard rowing/sailing dinghies offer much better options for kids (and towing).