Tribes is fun, but it's pay to win.
I played a fair bit of Tribes and I'm going ot have to disagree with this.
Tribes is certainly not pay to win. The default loadouts are mostly decent. There are things that you have to grind (or pay) for that have a large impact but winning without them is still quite possible. Similar to TF2 in that regard.
Buggy, unfinished and abandoned by the developer? Yes.
Pay to win? No.
Regardless of that, onwards to the popping of balls!