Takmo,
Unless you are going to spend a decent amount of your time trying to develop a hook, buying a high performance ball designed for experienced players may not be helpful to your game.
If you have a brand preference ( Storm, Ebonite, Brunswick, etc...), go to the shop and ask about their entry level or mid level balls.
The tropical you mention is Storm's entry level ball. Brunswick's Power Groove line is similar, as is Ebonites Tornado line and Columbia's new Jazz line.
Any of these balls will give you enough ball to use while learning the finer points of the game without spending a lot of bucks for performance POTENTIAL that you wouldn't be using anyway.
The mid-line balls will have a bit more performance POTENTIAL, but will also cost several maor bucks. They would let you use the same ball longer while improving your skills before reaching their full potential, but not necessarily out-perform the lower level balls until you have reached that level yourself.
More important than having several balls is having a good time. Go out there tonight, use whatever you have to the best of your abilities, and have FUN. That, my friend, is what it's all about.
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"The significant problems we face cannot be solved at the same level of thinking we were at when we created them."
Albert Einstein
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