Prevelo Alpha Three 20 Inch Kids Bike Review 

Both are really fantastic bikes. I wouldn't second guess the Frog 55 at all! The Prevelo Alpha has a lower standover height, so if you're child is still a little small for a 20" that's something to consider. Otherwise, if he'd prefer the Frog--go for it!

I get it. Just keep in mind that you should be able to get pretty good resale value out of the bike when you're done with it too.

Rascal Rides I went with a Woom bike for kids first bike, but can’t continue dropping the $475-500 price range. Looking at bikes in the $250-300 range, like Liv/Giant aluminum ones.

Both are fantastic bikes. The Prevelo Alpha 3 has a lower standover height than the Woom 4, so if your child is still on the smaller size, that can be a big differentiater. It also has a trigger shifter which I prefer to the grip shifter on the Woom. That said, the Woom is lighter which can make a huge difference for kids, especially when riding longer distances. You'll also get better resale value with the Woom.