Bopping -- although staggering like an overloaded pack mule is probably a more apt description -- frequently back and forth between Hong Kong and Shenzhen is almost always a study in contrasts, though not always the ones espoused by residents of either city, many of whom rely on crude, broad-brush stereotypes, urban myths and hearsay rather than first hand experience for their acquired wisdom regarding their border neighbors.

There are, of course, the obvious differences such as:

1. Public toilets. Hong Kong (check), Shenzhen (Whaa? Oh, I mean, first bush on the right...)

2. Low prices. Hong Kong (No one here gets out alive). Shenzhen (A copy-cat BMW For 800 yuan (US$100)? No problem! Can I throw in a fake F-17 fighter jet and a phony Prada clutch bag for an extra 75 yuan?)

3. Crowds. No contest. Hong Kong. (At about 7 million, Hong Kong is one of the most densely populated areas in the world, with an overall density of some 6,400 people per square kilometer.) Shenzhen (11 million, most of whom are "unregistered.") Still, there's still room to move except in nightclubs after 10pm and hot middle class shopping malls on weekends with a paltry 5,500 sweaty souls per square click.

4. Black-market organ harvesting. A toss-up. This cuts both ways, if you’ll excuse the pun. And it strikes to the heart (or kidney) of the misconceptions residents of both cities have about their counterparts. I first heard a version of this urban myth in the late 1990s in the United States. Kidney transplant in four easy steps. Step 4: Ensure the trash can doesn't contain any unnecessary intestines! Briefly told, a trusting rube checks into a Las Vegas hotel for the first time, has cocktails with a comely bar wench and awakens a day later in a bathtub full of ice with a missing memory and a missing kidney.

Fast-forward to Shenzhen 2004. “Oh, you go to Hong Kong often?” asked a startled Shenzhen resident. “Be very careful! My brother-in-law’s cousin’s friend went on business and was tricked by gangsters in a hotel who cut him open to sell his kidney.” More recently, last week in fact, one of Hong Kong’s leading scandal sheets, Apple Daily, printed a version of the same legend (complete with imagined illustrations) after callers to a Hong Kong radio talk show told the host that their female “friends” had gone to a popular spa and beauty clinic in Shenzhen only to meet the same gruesome fate in the spa’s restroom.

As it happens, I’ve accompanied my girlfriend to that same spa, and while I haven’t used the women’s restroom, I can attest that if it’s anything like the men’s room it barely has room to pull down your trousers, much less extract a kidney.

Hong Kong residents generally regard mainlanders as crafty, thieving cheapskate barbarians who unashamedly spit in public while in Shenzhen the stereotype of the uncultured, loutish, gold chain-bedecked Hong Kong businessman flashing a wad of Hong Kong dollars with one hand while the other paws an 18-year-old karaoke hostess holds sway. As neither, but an observer of both, I can say there’s a modicum of truth to these crude stereotypes but the greater truth is that they still have an awful lot to learn from one another.

It's the little things I learn when I'm back in Shenzhen that keep me on the proverbial learning curve regarding the bigger truths in China. My girlfriend, C, is the source for much of this, as in a recent casual exchange regarding shopping pals.

I've long since boxed myself in as her Most Trustworthy Shopping Partner and it's not due to my amazing shrinking wallet. Part of the initial courtship ritual involved a patient, loving sensitive guy approach -- "An afternoon spent mindlessly staggering like drug addled zombie lab rats through claustrophobic, deafening, identical malls offering merchandise available everywhere else on the planet, save Darfur or the Vostok Ice Station in Antarctica? "To experience something as spiritually and intellectually fulfilling as that? Especially with you, dear heart? Instead of swilling adult beverages and mindlessly bullshitting with my licentious, dissolute expat male buds? Aw, honey. You're kidding! Why did you even have to ask?" -- that I've been increasingly unable to convincingly maintain the role and, as such, have begun gently nudging her oh-so-gently towards the concept of galpal shopping. Giggling, flouncing, bouncing like spring fawns through a magical mystical wonderland o' retail bling-bling, leaving the guys behind to scratch their butts, fart, talk football and cranking up the AC/DC.

"I only have a few friends to shop with and I don't trust their judgment," she said recently. "Except one. And her work schedule is not regular."

This part caught my attention. I pressed further. "She's an accountant," C explained. "But she only does 'fake books.'"

In other words she specializes in cooking the books for Shenzhen businesses. I expressed mild surprise -- much as I would if C had said she'd rather watch ESPN replays of a 10-day old NFL game or have me lead her track-by-track through the new Who or Dylan releases rather than try on prohibitively expensive shoes for 6 hours. She was equally mildly amused at my naiveté, to say the least.

"It's very common. Many accountants here do it,” she said in the same tone of voice one might use when assuring a 2-year-old that the sun will indeed rise tomorrow.. “Almost every business has fake books. They only trust their family or relatives to do the real ones and hire people like my friend for the fake ones." It all reminded me of the time she'd told me she needed to help an ex-People's Liberation Army pal lock into some low-cost office supplies for the Hong Kong PLA garrison. On the surface China is the world's next super power. Economy growing to the point of overheating. Big inroads into future markets like Africa's energy resources. A couple of manned space shots. Respected international negotiating partner for problem spots a la North Korea. Huge World Trade Organization aspirations. Further proof of international validity? The first McDonald's in China -- long since a staple -- was established, complete with testimonial plaque -- in Shenzhen.

Yet most of the books are cooked down to the most basic level and the world's largest army can't figure out in-house logistics for office supplies in one of the world's most populated, supposedly cosmopolitan locales?

Meanwhile, across the border, in an almost continually smog-choked Hong Kong, Chief Executive Donald Tsang has proclaimed an “Action Blue Sky” campaign that amounts to nothing more than lip service, some vague promises regarding “public consultation” and a straight-faced proclamation that Hong Kong’s phlegm-colored skies compare favorably to those of Los Angeles and Tokyo. Maybe LA and Tokyo circa 1979, he didn’t add. It’s obvious he has either never visited either, or was simply lying and relying on the population’s general ignorance of the world outside their border.

It all looks fine to the naked eye, but it doesn’t really happen that way at all.