"Cheap as chips" means that something is extremely inexpensive. Is Retrax an expensive toy? It's a Deluxe and it was sold at the Deluxe price point. I don't think that's cheap or expensive... just normal. I wouldn't pay more than Deluxe price for this toy (then again, I don't like paying above RRP for any toy)
References
http://www.usingenglish.com/referenc...+as+chips.html
http://www.english-sayings.com/cheap-as-chips/6134
http://www.answers.com/topic/cheap
http://www.peevish.co.uk/slang/c.htm
http://www.ecenglish.com/learnenglis...english-idioms