TJF, that looks like a good 4 ball arsenal that should be able to cover the gammet of conditions. You may add another medium ball in there to give you a different look, say maybe a Rule or something.
BigWilly, you're definately in the minority there. The GP2 is an incredibly capable ball and extremely versatile as well. Even non Track fans have praised the ball's performance. On that note, I don't own one, but that doesn't mean I don't want one! I have an Animal that handles most oil I see, but there have been quite a few occasions where I could've used something a tad stronger; case in point, the GP2. You are entitled to your opinion, and this is mine.