I have met so many Calvinist professors and Teaching Assistants this year that it makes me wonder if it's a work of divine providence (I wish he'd send more Lutherans, I find their theology more tenable).
There are some things I love about this heresy that keep coming through. For example, Calvinists care about truth rather than hurting people's feelings. If you are a Calvinist and heard me call your religion a 'heresy' above, it probably didn't make you flinch because you don't even think Roman Catholicism is a Christian religion so what does it matter to you? Calvinists care about the truth, they believe in the truth of the Word of God and constantly remind me of it. I showed a Reformed TA today how the canon is based on Church authority and he still refrained "But it's the WORD!", the division between the Word of God and the words of even the greatest men is an infinite divide for the Calvinist (and I admire this in a sense I rarely like to admit).
As well, Calvinists actually believe in Original Sin. They believe that if God damned everyone to Hell without offering any salvation because of the Fall he would still be just and worthy of worship. Every orthodox christian should accept that premise but I feel like it's only the Conservative Calvinists and Traditional Catholics who still admit it. God owes nothing to us, we were born dead and in sin, we aren't good, we aren't lovable, but God loves us anyway.
Finally I have to say I like Calvinism's teaching about God's Sovereignty. This is the most tempting part of their theology. Salvation is God's business, it's up to him, in the words of St. Driscoll as they call him "God decides who comes inside his house". This allows a christian to fully embrace the sinfulness of man and the grace of God. Resistible grace while being a proud part of the Patristic and arguably biblical tradition is just weak. God is much cooler if he kicks the door down rather than knocking at the door (Rev 3).
I will not become a Calvinist though, because as appealing as it is in these areas, I still think it's a heresy. But one of the better heresies, not like Eastern Orthodoxy or Anabaptistism. But I don't think I'm allowed to call Orthodoxy a heresy... whoops. Whatever, I said it, in the spirit of Calvin. East Orthodox, pick up some St. Anselm and get on the Papal Supremacy train!