Crown Vics have a good reputation, and the engine is practically
indestructible. Be aware that it's a rear-wheel drive vehicle; not
necessarily the best choice for snowy winters.
The 98 year model had significant improvements in brakes, suspension and a
couple other items, compared to earlier years, so it seems a good choice.
The Police Interceptor is essentially a stripped down civilian version, with
some minor improvements to cooling and such, to allow high speed pursuits -
99% of the parts are shared with the civilian version, so they are
inexpensive and readily available. Buying a retired police car is a gamble,
though. It may be in perfect condition, or might have been badly abused,
gone through a few accidents, etc, etc. If you are considering buying it,
have it thoroughly inspected by a professional. And even so, the price you
offer should reflect its past. Go to www.crownic.net and ask there. It's
a site dedicated to Crown Vic enthusiasts.
By the way, if you are interested in this model and would rather have a nice
interior, cruise control, softer ride, and some other amenities instead of a
speedometer which goes to 180MPH or so, you may want to take a look at a
civilian version. It's going to cost you more, though.