The Saturn and the Venus are two of the best bang-for-your-buck balls out there right now -- and that does not mean, in any way, that they are "just entry level" balls. The hitting power of the Roto Planet line is right up there with the more expensive balls (unless you are bowling on, say, a 50 foot flat shot, which you are not, so it doesn't matter).
The Saturn and the Venus are a step up from the Power Grooves. The two piece core design, and the slightly more aggresive covers (Saturn is solid Sure Grip II, Venus is 1% load pearl particle Sure Grip II) will give you more overall hook potential. Still, the low differential and higher RG core will give you some length with an easy to control backend reaction.
Without a doubt, I would recommend either of those two Roto balls. Personally, I'm attached to my 1:30 leverage drilled Saturn, which I have at 1000 abralon with some polish. It is, as of right now, my go to ball whenever I get in trouble on the lanes. The Saturn always gives me a decent look -- it's no wonder it also has well over 200 games on it. You simply can't go wrong with one.
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I am the University of Virginia's Bowling Team. After all, one All-American is all you need.