[mgarblik]

"I’m not familiar with the Toyota’s as I don’t own one but our company has Chrysler minivan and it’s not smooth when it restarts; in anything it seems slow to restart and sounded like a starter.
I’d agree the Toyota might be robust but I wouldnt bet on the Chrysler; seems the repair cost will eat the fuel saving easily and then some when the time comes.
I just don’t like a vehicle that shuts down in traffic only to restart 2 seconds later."

I looked up some info on the Chrysler mini-van system 2020 and newer. You are mostly correct in your assessment of what it has going on under the hood. It uses a larger, more powerful, gear reduction starter and conventional ring gear on the flexplate. What is different it it has a clutch within the starter drive. When the engine stops, the starter drive engages but does not crank. When you release the brake pedal and the engine gets the start command, the piston near TDC get a squirt of fuel and a spark, and should start without needing the starter and the drive will retract. But what if none of the pistons have enough compression to light the fuel, which is possible? Then the starter will crank and help turn the engine to the next cylinder in the firing order and start the engine and so forth. I can see this being noisier and possibly a little jerky sometimes. Leave it to Chrysler. Fortunately, there is a button to disable the entire start/stop system at any time. But each time you drive the vehicle you have to disable it. It is a normally "on" switch. I am not advocating these systems as being good or bad. They are out there and if we want to own new vehicles or work on them as in my case, we have to understand and put up with them. If gas prices go through the roof, there may be a meaningful savings. I have no idea.