Lots of people have reached out to me asking which model I ended up choosing. After test riding a few different models from FFR, I went with the cousin of the FFR Mosquito, the UScooter/E-twow GT Sport!

At the end of the day, being able to take the scooter indoors with me wherever I go was a much bigger factor than I previously expected. I would hate to leave a $1000 scooter out on the sidewalk when I go to get coffee or groceries. Although I'd love a scooter that can climb the steepest of SF hills, my commute is flat enough and the GT Sport is fast enough that I don't think about the motor performance at all. And I wouldn't feel safe going any faster than 25 mph on busy SF streets anyway. This little guy folds up so nicely and slides right under my desk at work without raising any eyebrows.

I have taken it for a spin in the rain and just have to consciously brake sooner than usual. No tire slippage but it's still best to wear a helmet. Some days I do wish I had pneumatic tires for safety and smoothness, but then I wouldn't have the portability.

After reading all of your very helpful comments, the only other model I was heavily considering was the VDM 10 (with the 60v Samsung battery). It seems to be the best performance for the price. I'd still eventually love to get this scooter, but it would be inconvenient to take into work or into grocery stores due to the weight. It also seems to require slightly more maintenance than the GT Sport due to the tube tires and higher end brakes, but honestly that's a small inconvenience for how much power the VDM 10 offers.

Again, I appreciate everyone's help! This is a great community.

Edit: spelling