Continuing to ponder the theological intricacies of salvation and the atonement, as per the previous post:
On grace: As a natural implication of the doctrines of unconditional election and limited atonement, Calvinists also teach that the elect cannot resist His call, and that the Call can only be responded to with repentance and faith. As an implication of their theology, Arminians teach that grace may be made ineffectual by our lack of response. Again the notion of "wasted" grace pops up.
On perseverance: The Calvinist belief in eternal security makes sense given their belief presented above that grace cannot be resisted. Arminians belief that God provides grace for any emergency of faith, though it can be neglected by some to their eternal peril.
I confess that I love thinking about this stuff, and how one doctrinal point has to lead to another. At this point in my theological development, I lean a little bit toward the Arminian view of the world. I tend to have a "free will" bias in my thinking, a view that Jacob Arminius evidently shared.