Basically what you have learned is yes you can get a cheap cost of a bike up front at time of purchase but will eventually pay the same or close to the price of a bike at a bike shop over a short period of time due to poor quality. Purchasing a bike from the shop has benefits, 1 you get free maintenance checkups for the life of the bike and 2 their bikes most likely come with better rims that are true and will probably stay true with casual riding. Case in point: I bought a trek kids bike for my son 13 years ago from the shop at $130. At the time that was a lot for a 16" size kids bike and my wife said I paid too much. Well that bike has taken a beating and the rims never went out of true, Wheels spin like new and the cranks and headset are still perfect. It has gone through 3 kids and is still going strong. The only thing I replaced since then was tires, tubes and grips...Money well spent...