Whitecap I know you're not really looking for a dinghy motor, but I've had a Torqeedo 1003 for my RU3 inflatable dinghy for 3 seasons and love it.
The RU3 dinghy is a short (7.5') flat bottomed inflatable with a max HP rating of 4HP, so it's not an efficient hull form. I know it's not efficient when I try to row it!
The Travel 1003 can get my dinghy to just over 3 knots with 3 people aboard, and range is around 3-4 miles at this speed. Increasing speed to almost 4 knots makes lots of noise, sounding way faster, and decreases range to under 2 miles. Go slower in flat water and range increases significantly, and having the GPS display instantaneous speed and range on the tiller helps ease nervousness about range.
Storage is a huge plus. Since there's no fuel or oil to make a mess, I stow the motor below on a bunk after it dries. It can be installed by my girlfriend easily since it's lightweight, and is easily installed in pieces (motor installed on dinghy before battery). Operation is easy, too, with no choke or pull start. It's been very reliable for us, though it's a little sensitive to cables getting cross threaded as we assemble it. Rarely, we'll get an error message that a cable isn't connected properly that's fixed by disconnecting and reconnecting everything which takes less than 30 seconds. The magnetic safety cutout switch broke apart on us, too, though that's easily fixed with adhesive or even tape.
Biggest drawbacks: it's pretty expensive compared to traditional motors... by a lot. Also, charging from zero to full takes a while, though this has never really been a limiting factor for us. At night, or when sailing the big boat during the day, I connect the battery to a charging wire from the big boat's 12v system (yes, the charging input is 12v, even though the Torqeedo battery output is something like 36v).
The 1003 is a fairly small motor (under 4HP), so comparing this to a 10HP four stroke is not fair. I have no experience with the bigger Torqeedos.
Overall, we're happy with it, and I'd choose it again for our scenario.