A couple comments on that bike in particular. One disclaimer, I'm really not much of an expert on bikes, as regards equipment. I'm knowledgeable about biking, and mostly bike commuting. I can't comment on specific drivetrain components, brakes, that kind of thing. With that in mind, here goes....
I don't like aluminum frames much because they are usually pretty stiff. In fact the bike in your link is said to be stiff. Aluminum is lighter, and stiff bikes transfer pedal power to forward motion more readily but David you're not racing. I would go with something more resilient and comfortable, and generally this is found in a steel frame. The 1.75†tires will give you more comfort though than skinnier tires. But more friction too. For distance, in my opinion, you want a steel frame and skinnier tires, 28's or 33's (mm width).
Also, if you can handle drop bars, I really prefer them. Drop bars give you more hand positions than flat bars. On longer “exercise†rides, down in the park, if you are like me you are going to want to move your hands around. Flat bar bikes give you only one hand position. That's OK for five miles (I rode ten this morning with a flat bar bike, my “backup†bike) but for longer rides I think you'll get bored with flat bars (and the 26†wheels for that matter). I really can't emphasize this enough. Unless you have a bad back, and if you think you're pretty serious, favor the drop bars.
Since I brought up the wheels, I guess I don't consider a 26†bike to be a true road bike. Better to go with 700c, that's a larger diameter. And like I said narrower tires.
The GT in your link has “platform†pedals and my guess is that you will tire of them, and at a minimum want to add toe clips, and perhaps someday clipless pedals (for which you need special shoes). These other options let you “pull up†on one pedal while you are pressing down with the other. More exercise and more speed.
Remember, you will want to add a rear rack, lights, something for storage (panniers or a trunk bag), a decent lock and fenders to this bike. Plus a pump, spare tubes, a couple tire levers which are best housed in a wedge bag under your seat. What I am saying is you need to spend at least another $100, probably more.
I guess generally I think it's a mistake to buy an “all-purpose†bike which is what I think this GT purports to be. I would buy a bike you can commute with, AND take down to the park for a fast ride. When a bike also purports to be able to go off-road, the compromises you make to its commutability and road-worthiness are just too great, in my opinion. To me this bike seems like it really isn't particularly good at anything except maybe for modest commuting and getting around town. And if you were to take it off road its stiffness and lack of any suspension would become immediately apparent!
David I really think you should plan on spending more. I just don't think the bike you really want can be had for $200 or even $300, unless you luck into a used one. At a minimum I would go down to the bike co-op down in the Flats before I buy anything. Jim might have something perfect and if he did it would be a shame to miss out.
Here's the link. Perhaps the reason Spin didn't have anything in your price range is because there really isn't anything available that they feel comfortable recommending.
David how tall are you? I'll nose around a bit online. Craigslist, Ebay, but it's a bad time to be bargain hunting. You and thousands of others have noticed that spring is right around the corner.
FYI click here for an old thread on the bike forum regarding GT bikes. Generally it sounds like they are OK but certainly not great.
And click here, this is my commuter, most days. But not today, as I am rebuilding the rear wheel. I really like this bike. It cost me $649 but will last me a lifetime.
Bottom line, if what you want to do is ride back and forth to work, and around town, the GT will be fine. But in my opinion the day you want to take it down to the park and ride for 20 miles I think you will be very disappointed. I don't know about you, but every now and then, I just have the need for speed. An early morning ride down in the park on a fast bike is as close to flying as any human can feel. You won't get that feeling on the GT. And in fact for those rides, I have a third bike, a 35-year-old ten-speed, my boyhood bike. Like I said, I'm really not a believer in an “all-purpose†bike.
I hope I have been helpful without being harsh.
