I learned long ago that the best way to refute an adversary - is to see what he has to say. Chick never learned that message; he spouts biblical passages that seem to back him up, he uses only the most choice out-of-context pieces of a D&D manual to back himself up, and restates the same case over again.
Chick's essays are like a vaccination - it ain't pleasant, it can make you sick, but after having read it enough, you become inoculated to tripe, now knowing the worst of their arguments.
I will say one thing, that holds true for anyone with religious faith - anything that becomes a stumbling-block to your faith, is not good for your spiritual well-being - whether it's RPG's, fast cars, your job, or strawberry jam on toast. If one finds their faith being put second to something else in their lives, it's best to re-evaluate one's priorities.
However, it's not inherent in that thing - it's in how you use it, and how important that thing becomes to you compared to your faith. The old adage, "too much of any one thing is bad for you," has a lot of truth to it.