I would drill a 300C. The difference between a 607 and 505 is not that significantly difference. If you are having a hard time controlling the 607, though the 505 is "weaker", the cover is still going to be strong enough to hook quite a bit. If you step down to the 300, not only is is going to be weaker, it will also be much more controllable, and thus, much more playable. Plus, the 300 will still be more hook than entry level stuff.
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