Got the bike at a local Wal Mart. 100 bucks I think they've been discontinued though. My kit is from Powerkingshop on eBay. search around for Moon Dog on this site. There's several ppl with this bike.
The Mongoose looks pretty good compared to the Roadmaster as to quality. I would not bet on a 10 minute assembly and I have done it for a living. At least you are looking at some quality in the bike. I would like to see the finished assembly. What motor will go on there?