A suggestion: Read through the C & V forums to get an idea what is being presented, appraised, for sale, etc. This should give you some information about the quality and features of the various bikes and their components.
By-the-way, are you Italian? It was strange seeing a link to the Italian E-Bay.
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Remember: Real bikes have pedals.
...and never put a yellow tail on a Red, White and Blue kite!