I am a long time runner looking to add some bicycling to my workouts for some cross training and I would also use the bike to commute back and forth to work when the weather is nice, about 2 miles each way. I went to the local bike shop today and test rode 2 bikes, a Giant Cypress ST and a 2008 model Trek Fx 7.2. The Giant was more comfortable, the Trek felt like it was faster. If the bikes were the same price, I would pick the Trek. With tax and everything the Trek would cost me $490, the Giant $305. The salesperson acted like the Trek was quite a bit more bike and was steering me that way but I never trust a salesperson when they are steering you towards the more expensive item. Is the Trek $200 more bicycle than the Giant? Would the Giant suffice for workouts or do I need a faster bike like the Trek?

I think they are both good bikes I just don't want to buy a bike that's not going to do what I want to do nor do I want to buy a $500 bike when a $300 one will work. Any opinions would be appreciated. Thanks.