It's an interesting dilemma. My personal experience is that the verbal score is highly inaccurate in demonstrating one's English skill. It's specially true when it comes with a low writing score.
I'm also aware of people of different origins can excel in one section, but not the other. For example, Chinese and Indian students focus on the verbal section and often score very high.
But the writing section which is hard to do well without actually writing and really learning the language.
As for bench mark, I often use 4.5 for the writing and anything above 500 verbal is good. More importantly, I look at how that person expresses himself in the personal essay. And true to form, many students with 600+ verbal have some of the most horrible essays I have ever seen, filled with broken English.
So even if your scores pass the muster, it's hard to gauge your true English fluency. Some schools use TOEFL as control mechanism, some use phone interview.
If you know which programs you want to apply to, you can prepare accordingly. There is no safe score that works for all, except 800/800/6. This is where due diligence pays off.