You're spending enough money that you can't buy a =bad= bike, just one that is not the best suited for your purposes. Treks Giants and Cannondales are really good bikes as well and it certainly won't hurt to try some of those too.

I don't know anything about you except what you've posted here and all you know about me is that I'm an internet loudmouth. Given that, it sounds to me like you're on the right track. As a new rider, I believe you would be well served to pay attention to tire clearances and gearing. Most importantly, pay attention to fit.

Worry about a pound or two in bike weight when you're whippet thin and hammering with the fast group in your local club.

Finally, you're going to depend on your bike shop at first and they're part of what you're paying for. If you get great service from a helpful staff at one shop and not so much at another, then consider that in your choice.