In our 25-year, scary-long list of past boats, we have had all manner of dinghy engines - Honda 2, Nissann 4, Merc 3.5, Tohatsu 8, a Torqeedo 1003 and several others I have since forgotten.
Our cruising areas and needs at the time had us only ever needing to travel up to maybe 2 miles in the dinghy, so range was not much of an issue. The size of the big boats we had did not allow for much more dinghy or motor with regards to weight and size, either. No 12ft Caribe with 30hp and console for us!
All have their drawbacks. I had the 4-stroke carb disassemble/clean operation on the gas outboards down to about 15 minutes. Had to do it often, no matter how much Seafoam or other additives were used or gas run out. Fact of life for motors that may sit a couple of months unused.
The Torqeedo 1003 was really nice. I did have range anxiety, though, and it was a mite under powered with the dinghy we had at the time - relative to the pain of having a gas outboard. For those cases, the gas outboards won out for us, even with the constant carb headaches.
Now, we have a big enough boat to carry a little more weight. With the dinghy we chose, the USCG label indicated 8hp max. The only gas outboard I was willing to commit to was a true fuel injected version - no carbs to gum up. The smallest and lightest of those was Suzuki 9.9hp. Just under 100lbs. This engine is a dream from a running/starting everytime/carbureter(none) standpoint. Starts on 1 pull EVERY time, no matter how long it sits (because of the sealed EFI system) -- even after 4 months one time.
However, it was just too heavy for our dinghy and it was very hard to start for the admiral (the first few inches of that first pull is pretty tough). Moving it around (dinghy carried up on the deckhouse) for maintenance, etc. at 100lbs, combined with the fact that it was oversized for the dinghy, was just too much for me.
We just sold the Suzuki 9.9 (today), and I have ordered at Torqeedo Cruise 2.0 (5hp equiv) tiller model. the additional horsepower over the 1003 should be plenty for us. My range anxiety will be alleviated by putting two Relion Lithium batteries permanently in the dinghy's locker. The batteries in total will be 49lbs and will live in the locker permanently. This will give us 1920 Wh of power for the Cruise 2.0 at 24V. I estimate that it will do 6mph wide open for an hour, or 4-5mph for about 4, 6, maybe even 8 hours. This should be plenty for us. All in, the cost, with motor, batteries, and charger is about twice the cost of a new Suzuki 9.9. Ouch
We have a TON of solar (1.44KW) on the deckhouse and I am constantly looking for things to "spend" that power on once we are topped off on the house bank. Charging the two 75Ah 12V dinghy batteries via a remote cable will work great for this.
I also like the idea not having to find/carry gasoline anymore also. This all also assumes you don't NEED planing speeds (although the 5hp Torqeedo may get on a plane with just me in it - stay tuned!)
I will report back on speeds, range, etc. when I get the motor and parts and get everything hooked up and tested out.
Sorry to ramble on so......