Bonz_d is quite right. Much of it comes down to style and function. It's much like buying a car. They all do more or less the same thing so it's a matter of finding a good fit for you. I recently bought a 2012 Tracker Pro 165. It's a perfect fit for me. It fit my budget and my garage and has all the bells and whistles I need to get on the water. What it doesn't have I can add since I paid so little for it. It's not a big boat but it does well on open water with a few considerations. If what you're looking for is a small boat, the game fisher or the tracker, it will suit you fine in most conditions.
That said you may want to consider a couple of things. The game fisher is small and light and from what I can tell is basically a flat bottom boat or a modified v at most. The lighter your boat the more unstable it will be in choppy water. Flat bottom boats also are more unstable in choppy water. However, light flat bottom boats are comfortable and stable in calm water. A v hull tracker will be quite a bit heaver all the way around. It will handle choppy water much better. The deeper the v is in the hull the better it will handle choppy water at speed.
So a lot comes down to what you will use it for and where. Even on local lakes if the wind gets up around 20 mph the water is bad enough that my boat rides very rough and with even higher wind speeds or inclement weather it can take on water easily. But on calm or somewhat rough water it is all I will ever need. Consider where you will be using your boat. While a flat bottom game fisher will serve you well in calm conditions on small lakes, the tracker with its deeper v and heavier hull (and likely larger engine capacity) will serve you much better if the winds kick up or the weather turns on you.
My personal opinion is to give the tracker some thought. If it fits your budget then it will fit your needs better if you intend to take it on large lakes, encounter less than perfect weather, or need a faster more stable ride. If you intend to use it on smaller lakes in calm weather and you don't need to get anywhere fast, I'd give the game fisher some thought. It's likely cheaper and will be less of a financial strain making it easier to enjoy.
Think about what Bonz_d said. Consider style and function. Then consider where you will be using it and whether the combination of features will suit what you want to use it to do.
Out of curiosity, what model tracker are you looking at and for how much? I went with a new tracker a few years ago for my own reasons. I love the boat and don't regret the decision to buy it over an older used boat. Just curious what you're looking at.
I'll stop rambling now...