Any bike is easy to accessorize, through many sources. Don't get hung up on "brand" accessories - they are all the same when it comes to installation, and less known names cost less.

Get the bike that feels the best to you, and change it to how you want it. Trek and Specialized are both good - do they offer any other brands to compare them to?

Go for the 7.2 if you want the Trek - it's a better frame and has slightly better componentry.
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