I prefer the police package vehicles because of their beefier setups - stiffer springs, bigger sway bars, higher axle ratio, dual exhaust, engine oil cooler, ATF/PS cooler, higher capacity alternator and battery, bigger MAF sensor, etc. etc. the list goes on. The export variants of this platform were a win-win because they had all the creature comforts of their civilian counterparts plus the heavy duty components of the police variants. Earlier models had the Handling and Performance Package (HPP) with everything the police models had, only milder spring setups, but those are as common as hen's teeth now.
That being said, unless you're looking at a detective unit, a take home vehicle assigned to a single driver or an unmarked unit that hasn't seen much service use, you might want to pass unless you're getting a really sweet deal. Often they will be pretty well maintained but with 101 drivers who don't give a shoot, you'll get all sorts of cosmetic issues.
