We love Prevelo bikes. I started my kid on the Alpha Zero, when he was a tiny person, and now he is comfortable, confident, and loves bicycling. I picked Prevelo because of the reviews, but I loved that it came with a rear brake hand lever - something that hardly any balance bike comes with.
The website is easy to navigate, the customer service is excellent, and the trade up club is wonderful - I feel better about the higher price AND if he grows out of a bike faster than I expect, it is no big deal.
We moved from the Alpha Zero to the Alpha One, and now that my son is 4 and a half, he is zooming around on the Alpha Two.
I did a lot of research, and while there are cheaper bikes out there, they aren't equivalent quality, and many of them don't come with both front and rear hand levers. The way my son rides on dirt paths and down inclines - the hand lever brakes make for a much more precise ride.
If you want your kid to enjoy bicycling, ask to go bicycling instead of sitting around and watching TV, and to be confident and agile on his/her bicycle, then go for a Prevelo bike.